[Test] in workhorse:test go 1.15 and go 1.16

• https://gitlab.com/gitlab-org/gitlab/-/jobs/1219827714

--- FAIL: TestAllowedClone (82.18s)
    gitaly_integration_test.go:38: tcp://gitaly:8075
    gitaly_integration_test.go:90: 
        	Error Trace:	gitaly_integration_test.go:90
        	Error:      	Received unexpected error:
        	            	rpc error: code = Internal desc = CreateRepositoryFromURL: clone cmd wait: error: RPC failed; HTTP 503 curl 22 The requested URL returned error: 503
        	            	fatal: the remote end hung up unexpectedly
        	            	: exit status 128
        	Test:       	TestAllowedClone
--- FAIL: TestAllowedShallowClone (0.21s)
    gitaly_integration_test.go:38: tcp://gitaly:8075
    gitaly_integration_test.go:114: 
        	Error Trace:	gitaly_integration_test.go:114
        	Error:      	Received unexpected error:
        	            	rpc error: code = Internal desc = CreateRepositoryFromURL: clone cmd wait: fatal: unable to access 'https://gitlab.com/gitlab-org/gitlab-test.git/': The requested URL returned error: 503
        	            	: exit status 128
        	Test:       	TestAllowedShallowClone
--- FAIL: TestAllowedPush (75.30s)
    gitaly_integration_test.go:38: tcp://gitaly:8075
    main_test.go:773: 
    main_test.go:774: 
        	Error Trace:	main_test.go:774
        	            				gitaly_integration_test.go:149
        	Error:      	Received unexpected error:
        	            	chdir testdata/scratch/test: no such file or directory
        	Test:       	TestAllowedPush
time="2021-04-28T16:17:54Z" level=info msg=access content_type="text/plain; charset=utf-8" correlation_id=01F4CMBJ8BQ00P133AN22PHWZR duration_ms=3 host="127.0.0.1:39119" method=GET proto=HTTP/1.1 referrer= remote_addr="127.0.0.1:47628" remote_ip=127.0.0.1 route= status=200 system=http ttfb_ms=3 uri=/something user_agent=Go-http-client/1.1 written_bytes=1075
--- FAIL: TestAllowedGetGitArchive (37.85s)
    gitaly_integration_test.go:38: tcp://gitaly:8075
    gitaly_integration_test.go:191: 
        	Error Trace:	gitaly_integration_test.go:191
        	Error:      	Received unexpected error:
        	            	rpc error: code = Internal desc = CreateRepositoryFromURL: clone cmd wait: error: RPC failed; HTTP 502 curl 22 The requested URL returned error: 502
        	            	fatal: the remote end hung up unexpectedly
        	            	: exit status 128
        	Test:       	TestAllowedGetGitArchive

• https://gitlab.com/gitlab-org/gitlab/-/jobs/1219827718

--- FAIL: TestAllowedPush (31.73s)
    gitaly_integration_test.go:38: tcp://gitaly:8075
    gitaly_integration_test.go:138: 
        	Error Trace:	gitaly_integration_test.go:138
        	Error:      	Received unexpected error:
        	            	rpc error: code = Internal desc = CreateRepositoryFromURL: clone cmd wait: error: RPC failed; HTTP 502 curl 22 The requested URL returned error: 502
        	            	fatal: the remote end hung up unexpectedly
        	            	: exit status 128
        	Test:       	TestAllowedPush