Use correct refs for Ruby 2.7.

Update refs of rubygems from master to rawhide.

Resolves: rhbz#1965976

ruby.yaml

@@ -30,37 +30,37 @@ data:
                 rationale: An interpreter of object-oriented scripting language
                 multilib: [x86_64]
                 buildorder: 101
-                ref: master
+                ref: stream-ruby-2.7
             rubygem-abrt:
                 # From rubygem-abrt.spec Summary
                 rationale: >-
                     ABRT support for Ruby
                 buildorder: 102
-                ref: master
+                ref: rawhide
             rubygem-mysql2:
                 # From rubygem-mysql2.spec Summary
                 rationale: >-
                     A simple, fast Mysql library for Ruby, binding to libmysql
                 buildorder: 102
-                ref: master
+                ref: rawhide
             rubygem-pg:
                 # From rubygem-pg.spec Summary
                 rationale: >-
                     A Ruby interface to the PostgreSQL RDBMS
                 buildorder: 102
-                ref: master
+                ref: rawhide
             rubygem-bson:
                 # From rubygem-bson.spec Summary
                 rationale: >-
                     Ruby Implementation of the BSON specification
                 buildorder: 102
-                ref: master
+                ref: rawhide
             rubygem-mongo:
                 # From rubygem-mongo.spec Summary
                 rationale: >-
                     Ruby driver for MongoDB
                 buildorder: 103
-                ref: master
+                ref: rawhide
     buildopts:
         rpms:
             macros: |