1.2.3 Bump version in library.properties

What's Changed

• Update version number to 1.2.3 by @tyeth in #16

Full Changelog: 1.2.2...1.2.3

1.2.2 - Updated CI Actions versions

Update CI action versions

1.2.1 - Updated Adafruit_HMC5883_Unified::read()

Bump to 1.2.1

1.2.0 - Moved repository to GitHub Actions, fully documented with doxygen

Update README.md

1.1.0 - Added ATiny85 support, added PR and issue template

bumped to 1.1.0

1.0.0 release for Arduino

Automated initial release for Arduino library system.