Replace httpretty in tests

[emdneto]

Replace httpretty in tests. We should probably move to something else since it's abandoned for years. consider responses or pytest-httpserver

Originally posted by @emdneto in #4193

Instrumentations that need fixes:

• requests
• urllib (opentelemetry-instrumentation-urllib: switch from httpretty to pook #4282)
• urllib3 (opentelemetry-instrumentation-urllib3: convert tests to pook #4318)

[xrmx]

We can move to pook only after support for Python 3.10 is dropped 😿