feat: Add GIT_COMMITTER information to agent env vars (#1171)

This makes setting up git a bit simpler, and users
can always override these values!

We'll probably add a way to disable our Git integration
anyways, so these could be part of that.

coderd/workspaceagents_test.go

@@ -102,8 +102,6 @@ func TestWorkspaceAgentListen(t *testing.T) {
 	})
 	_, err = conn.Ping()
 	require.NoError(t, err)
-	_, err = agentClient.WorkspaceAgent(context.Background(), codersdk.Me)
-	require.NoError(t, err)
 }
 
 func TestWorkspaceAgentTURN(t *testing.T) {