feat: Sample everything 100% w/ Spotlight & no DSN set

[BYK]

This patch makes Spotlight easier to setup by turning all sampling to 100% when no DSN is set and Spotlight is enabled. I consider this a non-breaking and a safe change as these only apply when no DSN is set so it should have no production or billing implications.

[codecov]

❌ 1 Tests Failed:

Tests completed	Failed	Passed	Skipped
22323	1	22322	5593

View the top 1 failed test(s) by shortest run time

tests.integrations.grpc.test_grpc_aio test_grpc_server_abort

Stack Traces | 0.096s run time

.../integrations/grpc/test_grpc_aio.py:153: in test_grpc_server_abort
    assert len(events) == 1
E   assert 0 == 1
E    +  where 0 = len([])

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[szokeasaurusrex]

Nice! I have two suggestions, but since you'll likely have to implement them anyways in order to get the tests to pass, I'll approve

[szokeasaurusrex]

lgtm, see suggestion

[szokeasaurusrex]

I'm not quite sure why the GraphQL tests are failing here

[szokeasaurusrex]

Ah @sentrivana just pointed out in Slack that graphql tests are failing on master, so it might not be caused by this PR