feat(pymongo): introduce db.operation, refactor db.statement, refactor span name

[smoke]

Description

This change updates the opentelemetry-instrumentation-pymongo to better align with OpenTelemetry semantic conventions and the behavior of other language instrumentations (e.g. NodeJS, Ruby, etc.).

see https://github.com/open-telemetry/opentelemetry-js-contrib/blob/main/plugins/node/opentelemetry-instrumentation-mongodb/src/instrumentation.ts

The key changes are:

• The db.operation attribute is now used to record the MongoDB command name (e.g. find, insert).
• The db.statement attribute is no longer populated by default. It is only recorded if the capture_statement = True option is passed to the instrumentor.
• The span name has been made more specific, changing from {db_name}.{command} to {db_name}.{collection}.{command} when a collection is present.
• fixes Invalid type in attribute sequence when using sessions
  • fixes pymongo Invalid type in attribute sequence when using sessions #1918
  • closes issue 1918: Ensure string values for span status and attribute values #2010

This provides more consistent and conventional telemetry data for MongoDB operations.

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

The existing unit tests in instrumentation/opentelemetry-instrumentation-pymongo/tests/test_pymongo.py have been updated to reflect these changes.

Specifically, the tests now verify:

• db.operation is correctly set with the command name.
• db.statement is not present on the span by default.
• When capture_statement = True is enabled, db.statement is correctly populated with the full command statement.
• The span name is correctly formatted.

All tests were run and passed using the project's tox configuration:

tox -e test-pymongo

Does This PR Require a Core Repo Change?

• Yes. - Link to PR:
• No.

Checklist:

See contributing.md for styleguide, changelog guidelines, and more.

• Followed the style guidelines of this project
• Changelogs have been updated
• Unit tests have been added
• Documentation has been updated

[tammy-baylis-swi]

Thanks @smoke for working on improving adherence to semconv!

I think this should set db.operation.name rather than db.operation because SpanAttributes is deprecated. Meanwhile, I don't think db.operation.name is a direct replacement db.statement. Eventually, deprecated db.statement should be replaced by db.query.text and the value shouldn't completely go away.

Both attribute names could be updated similarly to the PRs that address this issue as a hard switch away from SpanAttributes: #3475. I'd suggest for a first PR for pymongo that we still keep db.statement and switch to db.query.text another time, but switch to the _incubating version instead of the SpanAttributes version like this asyncpg instrumentor PR. What do you think?