mr_list_test: Fix Test_mrListByTargetBranch
mr_list_test: Fix Test_mrListByTargetBranch

The Test_mrListByTargetBranch is failing with

--- FAIL: Test_mrListByTargetBranch (0.97s)
    mr_list_test.go:138:
        	Error Trace:	mr_list_test.go:138
        	Error:      	Not equal:
        	            	expected: "#1 Test MR for lab list"
        	            	actual  : "#6 test award emoji"

        	            	Diff:
        	            	--- Expected
        	            	+++ Actual
        	            	@@ -1 +1 @@
        	            	-#1 Test MR for lab list
        	            	+#6 test award emoji
        	Test:       	Test_mrListByTargetBranch

because test MR #6 was modified and now has an 'updated_at' date newer
than #1.

Change the Test_mrListByTargetBranch test so that it correctly detects #1
again.

Signed-off-by: Prarit Bhargava <fe4655370dc87a32329d591d6e8472329333dfad@redhat.com>

zaquestion/lab,zaquestion/lab