chore: bug is not a sufficient label (#5351)

Labels should correspond to a category in release-drafter.yml.

This actually happened in the wild: PR #5235 was dumped into a generic
"Changes" section of [release
0.55.0](https://github.com/vortex-data/vortex/releases/tag/0.55.0)
rather than the bug fix section.

Further in the past, #3587 was likewise uncategorized in
[0.40.0](https://github.com/vortex-data/vortex/releases/tag/0.40.0).

Signed-off-by: Daniel King <[email protected]>

Author: danking

.github/workflows/labels.yml

@@ -28,7 +28,6 @@ jobs:
         run: |
           REQUIRED_LABELS=(
             "chore"
-            "bug"
             "feature"
             "fix"
             "performance"