#15580 Alter invalid usage instruction in `@types/bluebird-global` (#15581)
#15580 Alter invalid usage instruction in `@types/bluebird-global` (#15581)

* Setting bluebird-global in compilerOptions.types
  is not required, so don't mention it in that
  tone in the docs
* Mention in the docs, that it's dev's
  responsibility to provide Bluebird in the
  runtime.

Closes #15580
magny/DefinitelyTyped,mcliment/DefinitelyTyped,smrq/DefinitelyTyped,nycdotnet/DefinitelyTyped,one-pieces/DefinitelyTyped,georgemarshall/DefinitelyTyped,georgemarshall/DefinitelyTyped,mcrawshaw/DefinitelyTyped,minodisk/DefinitelyTyped,jimthedev/DefinitelyTyped,mcrawshaw/DefinitelyTyped,AbraaoAlves/DefinitelyTyped,jimthedev/DefinitelyTyped,QuatroCode/DefinitelyTyped,aciccarello/DefinitelyTyped,AbraaoAlves/DefinitelyTyped,aciccarello/DefinitelyTyped,arusakov/DefinitelyTyped,ashwinr/DefinitelyTyped,rolandzwaga/DefinitelyTyped,johan-gorter/DefinitelyTyped,nycdotnet/DefinitelyTyped,AgentME/DefinitelyTyped,benishouga/DefinitelyTyped,chrootsu/DefinitelyTyped,arusakov/DefinitelyTyped,isman-usoh/DefinitelyTyped,YousefED/DefinitelyTyped,johan-gorter/DefinitelyTyped,AbraaoAlves/DefinitelyTyped,markogresak/DefinitelyTyped,ashwinr/DefinitelyTyped,benishouga/DefinitelyTyped,abbasmhd/DefinitelyTyped,jimthedev/DefinitelyTyped,abbasmhd/DefinitelyTyped,zuzusik/DefinitelyTyped,GiedriusGrabauskas/DefinitelyTyped,benishouga/DefinitelyTyped,dsebastien/DefinitelyTyped,AgentME/DefinitelyTyped,rolandzwaga/DefinitelyTyped,chrootsu/DefinitelyTyped,GiedriusGrabauskas/DefinitelyTyped,YousefED/DefinitelyTyped,dsebastien/DefinitelyTyped,smrq/DefinitelyTyped,QuatroCode/DefinitelyTyped,borisyankov/DefinitelyTyped,borisyankov/DefinitelyTyped,georgemarshall/DefinitelyTyped,alexdresko/DefinitelyTyped,benliddicott/DefinitelyTyped,zuzusik/DefinitelyTyped,amir-arad/DefinitelyTyped,arusakov/DefinitelyTyped,georgemarshall/DefinitelyTyped,magny/DefinitelyTyped,minodisk/DefinitelyTyped,AgentME/DefinitelyTyped,zuzusik/DefinitelyTyped,alexdresko/DefinitelyTyped,isman-usoh/DefinitelyTyped,laurentiustamate94/DefinitelyTyped,AgentME/DefinitelyTyped,aciccarello/DefinitelyTyped