Fix apmcloudutil logger assignment

[axw]

If logging isn't configured, apmlog.DefaultLogger will be nil. apmlog.DefaultLogger has a pointer-to-struct type, so converting it to apmcloudutil.Logger results in a non-nil interface value with a nil pointer value.

[apmmachine]

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• Start Time: 2021-11-25T01:07:53.405+0000

• Duration: 31 min 54 sec

• Commit: abc09a4

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Test	Results
Failed	0
Passed	11648
Skipped	268
Total	11916

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