Parses the given authorization header and returns the bearer token, or
undefined if no bearer token is given.
Parameters
authorizationHeader: unknown
Returns string|undefined
Remarks
This function is explicitly built to tolerate bad inputs safely, so you may
call it directly with e.g. the output of req.header('authorization')
without first checking that it exists.
Deprecated
Use the credentials method of HttpAuthService from @backstage/backend-plugin-api instead
Parses the given authorization header and returns the bearer token, or undefined if no bearer token is given.