Swarming: Tag metrics with swarming runtime.

[IvanBM18]

Currently if we run fuzzing sessions on swarming, the metrics dont seem to register those fuzzing hours correctly:

Note that the swarming fuzzing hours appear as empty: runtime=

• This PR adds swarming as a possible runtime
• Adds swarming in the error count metric
• Now that theres no circular dependency between logs <-> environment modules, i removed some methods that were previously declared twice to avoid said circular dependency, now they are correctly imported from a single module
• Also adds unit tests

Tests performed

Changes present in dev since before the last dev branch reset(which is around 22th of April).

Worth noting error logs in dev env:

Heres a list of logs that came to my attention:

There is a recurring PERMISSION_DENIED exception in the testcase_manager.py. It specifically points to "Missing or insufficient permissions" when calling the Datastore API via gRPC.

method: "_do_run_testcase_and_return_result_in_queue"
path: "/mnt/scratch0/clusterfuzz/src/clusterfuzz/_internal/bot/testcase_manager.py"
}
message: "Exception occurred while running run_testcase_and_return_result_in_queue.
Traceback (most recent call last):
  File "/mnt/scratch0/clusterfuzz/src/third_party/google/cloud/ndb/_datastore_api.py", line 98, in rpc_call
    result = yield rpc
             ^^^^^^^^^
	status = StatusCode.PERMISSION_DENIED
	details = "Missing or insufficient permissions."
	debug_error_string = "UNKNOWN:Error received "
>

Not related since we are not making any changes nor to auth or to the data store api.

raise RuntimeError('Request to %s failed. Code: %d. Reason: %s' %
RuntimeError: Request to https://storage.googleapis.com....
<Error><Code>SignatureDoesNotMatch</Code><Message>Access denied.</Message><Details>The request signature we calculated does not match the signature you provided. Check your Google secret key and signing method.</Details>

A weird error group, seems related to missing permissions or mismatch across service accounts, may be worth looking, or may come from other tests that someone is performing in dev

[IvanBM18]

Now that we dont have a circular dependency we can start using the same method that its declared on environment.py

[IvanBM18]

Same as above:
Now that we dont have a circular dependency we can start using the same method that its declared on environment.py

[jardondiego]

It looks like we have failing tests. Can you take a look?

[jardondiego]

LGTM

[letitz]

LGTM % nits.

Can you adjust the PR title? It does not describe what the change fixes. How about "Swarming: tag fuzzing hours metrics with correct runtime."?

[javanlacerda]

LGTM! Single question I have is if with this changes, the fuzzing hours for swarming are with the swarming label?