Merge Asterisk 20.3.0 into devel

.github/ISSUE_TEMPLATE/bug-report.yml

.github/ISSUE_TEMPLATE/config.yml

.github/ISSUE_TEMPLATE/improvement.yml

.github/ISSUE_TEMPLATE/new-feature.yml

.github/workflows/AsteriskReleaser.yml

.github/workflows/CherryPickTest.yml

.github/workflows/IssueOpened.yml

.github/workflows/NightlyAdmin.yml

.github/workflows/NightlyTests.yml

.github/workflows/PRMerged.yml

.github/workflows/PROpenedOrUpdated.yml

.gitignore

.gitreview

.version

BUGS

CHANGES.md

ChangeLogs/ChangeLog-20.3.0.md

ChangeLogs/historical/CHANGES

ChangeLogs/historical/ChangeLog

LICENSE