Prepare 1.2.0 release

[LossyDragon]

Description

I think it's time for a release! 🥳

Notable Changes:

• Add SteamApps.GetLegacyGameKey (#203)
• Add PlayingSessionStateCallback (#204)
• Remove sent/recv debug messages (#208)
• Fix websocket servers not being marked as bad by the server list (#209)
• Remove only_public from pics requests (#212)
• Update picsGetProductInfo (#212)
• Support UTF-8 encoding in PICSProductInfo (#213)
• Fix displaying newsitems child in SampleWebApi (#214)
• Target Java 8 and Gradle 7.6 (#216)
• Update protobufs and steamd (#217)
• Upload rpc methods as an interface (#217)
• Add error method to logger (#217)
• Allow the body to be set in ClientMsgProtobuf (#217)
• Allow MsgHdrProtoBuf to be visible, minor cleanup (#217)
• Add Support for SteamUnifiedMessages (#217)
• Implement Auth (for the new Steam login flow) (#217)
• Send client hello on connect (#222)
• Fix KeyValue.loadFromFile from crashing when loading a file (#224)

Other:

• Remove CodeCov and CircleCI, replaced with Github Actions
• Reorganized bug report and pull request templates
• Readme updates
• gitignore updates
• Various lint cleanup, spelling fixes, javadoc updates, finalize variables that are not mutable

Checklist

• Code compiles correctly
• All tests passing
• Samples run successfully
• Extended the README / documentation, if necessary