doc: minor fixes (aws-powertools#168)

chore: Prepare for 0.6.0-beta (aws-powertools#155)

chore: Prepare for 0.5.0-beta (aws-powertools#124)

ci: Prepare for 0.4.0-beta (aws-powertools#116)

ci: preparing release v0.3.1-beta (aws-powertools#107)

ci: preparing release v0.3.0-beta (aws-powertools#100)

ci: preparing realease v0.2.0-beta (aws-powertools#73)

ci: fixing Sonatype serverId (aws-powertools#57)