[PATCH v2 2/6] CI: use shorter names that fit in UX tooltips

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

Change the names used for the GitHub CI workflows to be short enough
to (mostly) fit in the pop-up tool-tips that GitHub shows in the
commit view. I.e. when mouse-clicking on the passing or failing
check-mark next to the commit subject.

These names are seemingly truncated to 17-20 characters followed by
three dots ("..."). Since a "CI/PR / " prefix is added to them the job
names looked like this before (windows-test and vs-test jobs omitted):

    CI/PR / ci-config (p...
    CI/PR / windows-buil...
    CI/PR / vs-build (pu...
    CI/PR / regular (lin...
    CI/PR / regular (lin...
    CI/PR / regular (os...
    CI/PR / regular (os...
    CI/PR / regular (lin...
    CI/PR / regular (lin...
    CI/PR / dockerized (...
    CI/PR / dockerized (...
    CI/PR / dockerized (...
    CI/PR / static-anal...
    CI/PR / sparse (pu...
    CI/PR / documenta...

By omitting the "/PR" from the top-level name, and pushing the
$jobname to the front we'll now instead get:

    CI / config (push)
    CI / win build (push...
    CI / win+VS build (...
    CI / linux-clang (ub...
    CI / linux-gcc (ubun...
    CI / osx-clang (osx)...
    CI / osx-gcc (osx) (...
    CI / linux-gcc-defau...
    CI / linux-leaks (ub...
    CI / linux-musl (alp...
    CI / Linux32 (daald/...
    CI / pedantic (fedor...
    CI / static-analysis...
    CI / sparse (push)...
    CI / documentation

We then have no truncation in the expanded view. See [1] for how it
looked before, [2] for a currently visible CI run using this commit,
and [3] for the GitHub workflow syntax involved being changed here.

Let's also add a field for the "os" and use it where appropriate, it's
occasionally useful to know we're running on say ubuntu
v.s. fedora (but the "-latest" suffix isn't very useful, that applies
to almost all the jobs.

1. https://github.com/git/git/tree/master/
2. https://github.com/avar/git/tree/avar/ci-rm-travis-cleanup-ci-names-2
3. https://docs.github.com/en/actions/learn-github-actions/workflow-syntax-for-github-actions

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 .github/workflows/main.yml | 16 +++++++++++++++-
 README.md                  |  2 +-
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 6ed6a9e8076..612b475fd0b 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -1,4 +1,4 @@
-name: CI/PR
+name: CI
 
 on: [push, pull_request]
 
@@ -7,6 +7,7 @@ env:
 
 jobs:
   ci-config:
+    name: config
     runs-on: ubuntu-latest
     outputs:
       enabled: ${{ steps.check-ref.outputs.enabled }}${{ steps.skip-if-redundant.outputs.enabled }}
@@ -77,6 +78,7 @@ jobs:
             }
 
   windows-build:
+    name: win build
     needs: ci-config
     if: needs.ci-config.outputs.enabled == 'yes'
     runs-on: windows-latest
@@ -97,6 +99,7 @@ jobs:
         name: windows-artifacts
         path: artifacts
   windows-test:
+    name: win test
     runs-on: windows-latest
     needs: [windows-build]
     strategy:
@@ -127,6 +130,7 @@ jobs:
         name: failed-tests-windows
         path: ${{env.FAILED_TEST_ARTIFACTS}}
   vs-build:
+    name: win+VS build
     needs: ci-config
     if: needs.ci-config.outputs.enabled == 'yes'
     env:
@@ -178,6 +182,7 @@ jobs:
         name: vs-artifacts
         path: artifacts
   vs-test:
+    name: win+VS test
     runs-on: windows-latest
     needs: vs-build
     strategy:
@@ -210,6 +215,7 @@ jobs:
         name: failed-tests-windows
         path: ${{env.FAILED_TEST_ARTIFACTS}}
   regular:
+    name: ${{matrix.vector.jobname}} (${{matrix.vector.os}})
     needs: ci-config
     if: needs.ci-config.outputs.enabled == 'yes'
     strategy:
@@ -218,21 +224,27 @@ jobs:
         vector:
           - jobname: linux-clang
             cc: clang
+            os: ubuntu
             pool: ubuntu-latest
           - jobname: linux-gcc
             cc: gcc
+            os: ubuntu
             pool: ubuntu-latest
           - jobname: osx-clang
             cc: clang
+            os: osx
             pool: macos-latest
           - jobname: osx-gcc
             cc: gcc
+            os: osx
             pool: macos-latest
           - jobname: linux-gcc-default
             cc: gcc
+            os: ubuntu
             pool: ubuntu-latest
           - jobname: linux-leaks
             cc: gcc
+            os: ubuntu
             pool: ubuntu-latest
     env:
       CC: ${{matrix.vector.cc}}
@@ -251,6 +263,7 @@ jobs:
         name: failed-tests-${{matrix.vector.jobname}}
         path: ${{env.FAILED_TEST_ARTIFACTS}}
   dockerized:
+    name: ${{matrix.vector.jobname}} (${{matrix.vector.image}})
     needs: ci-config
     if: needs.ci-config.outputs.enabled == 'yes'
     strategy:
@@ -310,6 +323,7 @@ jobs:
       run: ci/install-dependencies.sh
     - run: make sparse
   documentation:
+    name: documentation
     needs: ci-config
     if: needs.ci-config.outputs.enabled == 'yes'
     env:
diff --git a/README.md b/README.md
index eb8115e6b04..f6f43e78deb 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-[![Build status](https://github.com/git/git/workflows/CI/PR/badge.svg)](https://github.com/git/git/actions?query=branch%3Amaster+event%3Apush)
+[![Build status](https://github.com/git/git/workflows/CI/badge.svg)](https://github.com/git/git/actions?query=branch%3Amaster+event%3Apush)
 
 Git - fast, scalable, distributed revision control system
 =========================================================
-- 
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