[stubsabot] Bump regex to 2026.2.28

Release: https://pypi.org/pypi/regex/2026.2.28
Homepage: https://github.com/mrabarnett/mrab-regex
Repository: https://github.com/mrabarnett/mrab-regex
Typeshed stubs: https://github.com/python/typeshed/tree/main/stubs/regex
Diff: mrabarnett/mrab-regex@2026.2.19...2026.2.28

Stubsabot analysis of the diff between the two releases:
 - 0 public Python files have been added.
 - 0 files included in typeshed's stubs have been deleted.
 - 1 file included in typeshed's stubs has been modified or renamed: `regex/_main.py`.
 - Total lines of Python code added: 1.
 - Total lines of Python code deleted: 1.

If stubtest fails for this PR:
- Leave this PR open (as a reminder, and to prevent stubsabot from opening another PR)
- Fix stubtest failures in another PR, then close this PR

Note that you will need to close and re-open the PR in order to trigger CI

Author: stubsabot

stubs/regex/METADATA.toml

@@ -1,2 +1,2 @@
-version = "2026.2.19"
+version = "2026.2.28"
 upstream_repository = "https://github.com/mrabarnett/mrab-regex"