chore: remove deprecated items (#6580)

This PR adds a note to upgrade to 2.x in `upgrading.rst` and removes all
deprecated items slated for removal in 2.0.0. This includes:

- `DD_GEVENT_PATCH_ALL`: no special configuration is now necessary to
make `ddtrace-run` work with gevent.
- `DD_AWS_TAG_ALL_PARAMS`: the boto/botocore/aiobotocore integrations no
longer collect all API parameters by default.
- `DD_REMOTECONFIG_POLL_SECONDS`: replaced by
`DD_REMOTE_CONFIG_POLL_INTERVAL_SECONDS`
- ASM deprecated constants including ``APPSEC_ENABLED``,
``APPSEC_JSON``, ``APPSEC_EVENT_RULE_VERSION``,
``APPSEC_EVENT_RULE_ERRORS``,
``APPSEC_EVENT_RULE_LOADED``, ``APPSEC_EVENT_RULE_ERROR_COUNT``,
``APPSEC_WAF_DURATION``, ``APPSEC_WAF_DURATION_EXT``,
``APPSEC_WAF_TIMEOUTS``, ``APPSEC_WAF_VERSION``,
``APPSEC_ORIGIN_VALUE``, ``APPSEC_BLOCKED``,
``IAST_JSON``, ``IAST_ENABLED``, ``IAST_CONTEXT_KEY``. These constants
were meant for private use only and should not affect existing code.
- ``ddtrace.contrib.grpc.constants.GRPC_PORT_KEY``: replaced by
`ddtrace.ext.net.TARGET_PORT`
- ``ddtrace.ext.cassandra.ROW_COUNT``, ``ddtrace.ext.mongo.ROW_COUNT``,
``ddtrace.ext.sql.ROW_COUNT``: replaced by `ddtrace.ext.db.ROWCOUNT`
- `ddtrace.filters.TraceCiVisibilityFilter`: removed as this was for
private use only and does not affect existing code.
- `ddtrace.contrib.starlette.get_resource` and
`ddtrace.contrib.starlette.span_modifier` and
`ddtrace.contrib.fastapi.span_modifier`: the fastapi and starlette
integrations now provide the full route and not just mounted route for
sub-applications by default.
- `ddtrace.contrib.starlette.config['aggregate_resources']` and
`ddtrace.contrib.fastapi.config['aggregate_resources']`: the starlette
and fastapi integrations no longer have the option to aggregate
resources as this occurs by default now.
- `DD_TRACE_OBFUSCATION_QUERY_STRING_PATTERN`: replaced by
`DD_TRACE_OBFUSCATION_QUERY_STRING_REGEXP`.

Additionally, the `pep562` dependency and references to it have been
removed as it is no longer needed after dropping support for Python <
3.7.

Note that `DD_CALL_BASIC_CONFIG` and `DD_LOG_FORMAT` are removed in

- [x] Change(s) are motivated and described in the PR description.
- [x] Testing strategy is described if automated tests are not included
in the PR.
- [x] Risk is outlined (performance impact, potential for breakage,
maintainability, etc).
- [x] Change is maintainable (easy to change, telemetry, documentation).
- [x] [Library release note
guidelines](https://ddtrace.readthedocs.io/en/stable/releasenotes.html)
are followed. If no release note is required, add label
`changelog/no-changelog`.
- [x] Documentation is included (in-code, generated user docs, [public
corp docs](https://github.com/DataDog/documentation/)).
- [x] Backport labels are set (if
[applicable](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting))

- [x] Title is accurate.
- [x] No unnecessary changes are introduced.
- [x] Description motivates each change.
- [x] Avoids breaking
[API](https://ddtrace.readthedocs.io/en/stable/versioning.html#interfaces)
changes unless absolutely necessary.
- [x] Testing strategy adequately addresses listed risk(s).
- [x] Change is maintainable (easy to change, telemetry, documentation).
- [x] Release note makes sense to a user of the library.
- [x] Reviewer has explicitly acknowledged and discussed the performance
implications of this PR as reported in the benchmarks PR comment.
- [x] Backport labels are set in a manner that is consistent with the
[release branch maintenance
policy](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting)

releasenotes/notes/release-2.0-3af0045e2261bd02.yaml

@@ -5,7 +5,6 @@ prelude: >
   versions of the ddtrace library, drops support for Python 2.7, 3.5, and 3.6, and adds support for Python 3.12.
 
 
-
   .. important::
     ddtrace v2.0.0 drops support for Python 2.7, 3.5, and 3.6. Users running these unsupported
     Python versions should consider upgrading their Python version or continue using ddtrace v1