[rake][release_date] Make regex on "unreleased" case-insensitive (#719)
[rake][release_date] Make regex on "unreleased" case-insensitive (#719)


serverdensity/sd-agent-core-plugins,serverdensity/sd-agent-core-plugins,DataDog/integrations-core,itsuugo/integrations-core,DataDog/integrations-core,serverdensity/sd-agent-core-plugins,itsuugo/integrations-core,s-maj/integrations-core,DataDog/integrations-core,DataDog/integrations-core,s-maj/integrations-core,DataDog/integrations-core,serverdensity/sd-agent-core-plugins,varlib1/servermall,itsuugo/integrations-core,varlib1/servermall,varlib1/servermall,DataDog/integrations-core,s-maj/integrations-core,varlib1/servermall,serverdensity/sd-agent-core-plugins,DataDog/integrations-core,varlib1/servermall,s-maj/integrations-core,DataDog/integrations-core,DataDog/integrations-core,DataDog/integrations-core,itsuugo/integrations-core,s-maj/integrations-core,itsuugo/integrations-core