Added group saved replies GraphQL mutations

app/graphql/mutations/saved_replies/base.rb

app/graphql/mutations/saved_replies/create.rb

app/graphql/mutations/saved_replies/destroy.rb

app/graphql/mutations/saved_replies/update.rb

app/graphql/mutations/users/saved_replies/create.rb

app/graphql/mutations/users/saved_replies/destroy.rb

app/graphql/mutations/users/saved_replies/update.rb

app/graphql/types/mutation_type.rb

doc/api/graphql/reference/index.md

ee/app/graphql/ee/types/mutation_type.rb

ee/app/graphql/mutations/groups/saved_replies/create.rb

ee/app/graphql/mutations/groups/saved_replies/destroy.rb

ee/app/graphql/mutations/groups/saved_replies/update.rb

ee/app/policies/ee/group_policy.rb

ee/spec/policies/group_policy_spec.rb

.../requests/api/graphql/groups/saved_replies/create_spec.rb

...requests/api/graphql/groups/saved_replies/destroy_spec.rb

.../requests/api/graphql/groups/saved_replies/update_spec.rb

spec/graphql/mutations/users/saved_replies/create_spec.rb

spec/graphql/mutations/users/saved_replies/destroy_spec.rb