[RELEASE] - Bump version to 3.21.0

[RELEASE] - Bump version to 3.20.0

[RELEASE] - Bump version to 3.19.4

[RELEASE] - Bump version to 3.21.0.CR1

[RELEASE] - Bump version to 3.20.0.CR1

[RELEASE] - Bump version to 3.19.3

[RELEASE] - Bump version to 3.15.4

[RELEASE] - Bump version to 3.19.2

[RELEASE] - Bump version to 3.15.3.1

[RELEASE] - Bump version to 3.8.6.1