Sync eng/common directory with azure-sdk-tools for PR 1633 (#14757)
Sync eng/common directory with azure-sdk-tools for PR 1633 (#14757)

* Update format of new Changelog Entry

* Add parsing of changelog sections

* Update ChangeLog Logic

Co-authored-by: Chidozie Ononiwu <301d19fba573b360a93464351d7ca3ed97357016@microsoft.com>
Azure/azure-sdk-for-go,Azure/azure-sdk-for-go,Azure/azure-sdk-for-go,Azure/azure-sdk-for-go