Use gh workflow for tests (#41384)

Follow up for: #41304

Splits CI tests (cherry-picks and PRs only for now) into separate
workflows using `gh-workflow`. Includes a couple restructures to
- run more things in parallel
- remove our previous shell script based checking to filter tests based
on files changed, instead using the builtin `paths:` workflow filters


Splitting the docs/style/rust tests & checks into separate workflows
means we lose the complete summary showing all the tests in one view,
but it's possible to re-add in the future if we go back to checking what
files changed ourselves or always run everything.

Release Notes:

- N/A *or* Added/Fixed/Improved ...

---------

Co-authored-by: Conrad <conrad@zed.dev>

.github/workflows/run_bundling.yml

@@ -109,10 +109,10 @@ jobs:
       uses: matbour/setup-sentry-cli@3e938c54b3018bdd019973689ef984e033b0454b
       with:
         token: ${{ secrets.SENTRY_AUTH_TOKEN }}
-    - name: ./script/linux
+    - name: steps::setup_linux
       run: ./script/linux
       shell: bash -euxo pipefail {0}
-    - name: ./script/install-mold
+    - name: steps::install_mold
       run: ./script/install-mold
       shell: bash -euxo pipefail {0}
     - name: ./script/bundle-linux
@@ -143,9 +143,12 @@ jobs:
       uses: matbour/setup-sentry-cli@3e938c54b3018bdd019973689ef984e033b0454b
       with:
         token: ${{ secrets.SENTRY_AUTH_TOKEN }}
-    - name: ./script/linux
+    - name: steps::setup_linux
       run: ./script/linux
       shell: bash -euxo pipefail {0}
+    - name: steps::install_mold
+      run: ./script/install-mold
+      shell: bash -euxo pipefail {0}
     - name: ./script/bundle-linux
       run: ./script/bundle-linux
       shell: bash -euxo pipefail {0}