Remove unused Gitlab::Git.committer_hash

This was changed in gitaly-ruby, and rather than backporting that
change to Rails we just inline the hashes in the specs.

The `time` is not needed in the specs either, so we only specify the
`email` and `name`.

lib/gitlab/git.rb

@@ -35,16 +35,6 @@ module Gitlab
         end
       end
 
-      def committer_hash(email:, name:)
-        return if email.nil? || name.nil?
-
-        {
-          email: email,
-          name: name,
-          time: Time.now
-        }
-      end
-
       def tag_name(ref)
         ref = ref.to_s
         if self.tag_ref?(ref)

spec/lib/gitlab/git/branch_spec.rb

@@ -71,9 +71,7 @@ describe Gitlab::Git::Branch, :seed_helper do
     end
 
     let(:user) { create(:user) }
-    let(:committer) do
-      Gitlab::Git.committer_hash(email: user.email, name: user.name)
-    end
+    let(:committer) { { email: user.email, name: user.name } }
     let(:params) do
       parents = [rugged.head.target]
       tree = parents.first.tree

spec/lib/gitlab/git_spec.rb

@@ -6,32 +6,6 @@ describe Gitlab::Git do
   let(:committer_email) { 'user@example.org' }
   let(:committer_name) { 'John Doe' }
 
-  describe 'committer_hash' do
-    it "returns a hash containing the given email and name" do
-      committer_hash = described_class.committer_hash(email: committer_email, name: committer_name)
-
-      expect(committer_hash[:email]).to eq(committer_email)
-      expect(committer_hash[:name]).to eq(committer_name)
-      expect(committer_hash[:time]).to be_a(Time)
-    end
-
-    context 'when email is nil' do
-      it "returns nil" do
-        committer_hash = described_class.committer_hash(email: nil, name: committer_name)
-
-        expect(committer_hash).to be_nil
-      end
-    end
-
-    context 'when name is nil' do
-      it "returns nil" do
-        committer_hash = described_class.committer_hash(email: committer_email, name: nil)
-
-        expect(committer_hash).to be_nil
-      end
-    end
-  end
-
   describe '.ref_name' do
     it 'ensure ref is a valid UTF-8 string' do
       utf8_invalid_ref = Gitlab::Git::BRANCH_REF_PREFIX + "an_invalid_ref_\xE5"

spec/workers/git_garbage_collect_worker_spec.rb

@@ -230,8 +230,8 @@ describe GitGarbageCollectWorker do
     new_commit_sha = Rugged::Commit.create(
       rugged,
       message: "hello world #{SecureRandom.hex(6)}",
-      author: Gitlab::Git.committer_hash(email: 'foo@bar', name: 'baz'),
-      committer: Gitlab::Git.committer_hash(email: 'foo@bar', name: 'baz'),
+      author: { email: 'foo@bar', name: 'baz' },
+      committer: { email: 'foo@bar', name: 'baz' },
       tree: old_commit.tree,
       parents: [old_commit]
     )