Drop manylinux2014 from the build matrix.

Bumping to `actions/checkout@v4` broke it because it can't run the Node
20 binary. Its EOL is still a few months away, apparently, but updating
to Node 20 probably can't wait that long. C'est la vie.

Change-Id: Icf2bbd676583352f323cdac3056b4c8bebbbb07d
Reviewed-on: https://code-review.googlesource.com/c/re2/+/62511
Reviewed-by: Alex Chernyakhovsky <achernya@google.com>
Reviewed-by: Paul Wankadia <junyer@google.com>

.github/workflows/python.yml

@@ -23,7 +23,7 @@ jobs:
         arch:
           - { name: X64,   python-name: x86_64,  runs-on: [ubuntu-latest]             }
           - { name: ARM64, python-name: aarch64, runs-on: [self-hosted, linux, arm64] }
-        os: [manylinux2014, manylinux_2_28]
+        os: [manylinux_2_28]
         ver: ['3.8', '3.9', '3.10', '3.11', '3.12']
     env:
       BAZELISK_GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}