fix(ci): Run CI tests on all submodules

[cpheps]

Proposed Change

Temporary fix to ensure tests are being run on all submodules as the previous script to find submodules would not work on windows.

Checklist

• Changes are tested
• CI has passed

[BinaryFissionGames]

Looks like varnish tests fail on windows since the error messages returned aren't the exact same as on linux:

--- FAIL: TestValidate (0.00s)
    --- FAIL: TestValidate/missing_exec_dir (0.00s)
        config_test.go:70: 
            	Error Trace:	config_test.go:70
            	Error:      	Error message not equal:
            	            	expected: "\"exec_dir\" does not exists \"stat missing/exec: no such file or directory\""
            	            	actual  : "\"exec_dir\" does not exists \"CreateFile missing/exec: The system cannot find the path specified.\""
            	Test:       	TestValidate/missing_exec_dir
    --- FAIL: TestValidate/missing_working_dir (0.00s)
        config_test.go:70: 
            	Error Trace:	config_test.go:70
            	Error:      	Error message not equal:
            	            	expected: "\"working_dir\" does not exists \"stat missing/working: no such file or directory\""
            	            	actual  : "\"working_dir\" does not exists \"CreateFile missing/working: The system cannot find the path specified.\""
            	Test:       	TestValidate/missing_working_dir
    --- FAIL: TestValidate/missing_exec_and_working_dir (0.00s)
        config_test.go:70: 
            	Error Trace:	config_test.go:70
            	Error:      	Error message not equal:
            	            	expected: "\"working_dir\" does not exists \"stat missing/working: no such file or directory\"; \"exec_dir\" does not exists \"stat missing/exec: no such file or directory\""
            	            	actual  : "\"working_dir\" does not exists \"CreateFile missing/working: The system cannot find the path specified.\"; \"exec_dir\" does not exists \"CreateFile missing/exec: The system cannot find the path specified.\""
            	Test:       	TestValidate/missing_exec_and_working_dir
FAIL
FAIL	github.com/observiq/observiq-otel-collector/receiver/varnishreceiver	0.0[60](https://github.com/observIQ/observiq-otel-collector/runs/5648134972?check_suite_focus=true#step:7:60)s

but that proves that the tests DO run on windows, at least.