v1.2.0: Bug Fixes and Enhancements

[smusali]

This Pull Request contains the following changes:

• Add Newer Release Pipeline capturing 2 test cases
• Update Adapter Configuration
• Update Flush Mechanism
• Update HTTP Client by using heimdall which has built-in Retry Mechanism
• Add User Agent information into the Request Header

Tested with our sample Docker Compose test. Can be tested with samirmusali/logspout:latest

[smusali]

@teriyakichild @mrjohnnychang can you test samirmusali/logspout:latest against the issues you have been having in LogSpout? Thanks in advance!

[smusali]

@mindjiver @matt-march @CJP10

guys, can you do a final round of review? fixed some bugs and tested with existing docker compose test

Thanks in advance!