v6.12.0

IMPROVEMENTS:

• resource/signalfx_aws_integration: Add sync_custom_namespaces_only option #366
• resource/signalfx_aws_integration: documentation update (sorted arguments alphabetically) #368
• resource/signalfx_azure_integration: documentation update (described named_token parameter, sorted arguments alphabetically) #368
• resource/signalfx_gcp_integration: documentation update (described named_token parameter, sorted arguments alphabetically) #368