Release v4.1.1

Fixes

• Allow colon inside source tags by @jhamon in #351
• [grpc] Allow retries of up to MAX_MSG_SIZE by @daverigby in #347

Dependabot security updates

• Bump requests (dev-only dependency) from 2.31.0 to 2.32.3 by @jhamon in #352

Chores

• Remove unused constants by @jhamon in #350
• Wire up plugin interface by @jhamon in #353

Full Changelog: v4.1.0...v4.1.1