chore: remove deprecated items

[Yun-Kim]

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 #6612 which includes a subtle change in functionality.

Checklist

• Change(s) are motivated and described in the PR description.
• Testing strategy is described if automated tests are not included in the PR.
• Risk is outlined (performance impact, potential for breakage, maintainability, etc).
• Change is maintainable (easy to change, telemetry, documentation).
• Library release note guidelines are followed. If no release note is required, add label changelog/no-changelog.
• Documentation is included (in-code, generated user docs, public corp docs).
• Backport labels are set (if applicable)

Reviewer Checklist

• Title is accurate.
• No unnecessary changes are introduced.
• Description motivates each change.
• Avoids breaking API changes unless absolutely necessary.
• Testing strategy adequately addresses listed risk(s).
• Change is maintainable (easy to change, telemetry, documentation).
• Release note makes sense to a user of the library.
• Reviewer has explicitly acknowledged and discussed the performance implications of this PR as reported in the benchmarks PR comment.
• Backport labels are set in a manner that is consistent with the release branch maintenance policy

[pr-commenter]

Benchmarks

Benchmark execution time: 2023-08-31 17:41:48

Comparing candidate commit a1b047f in PR branch yunkim/remove-deprecated-items with baseline commit 76f6851 in branch 2.x-dev.

Found 6 performance improvements and 7 performance regressions! Performance is the same for 91 metrics, 0 unstable metrics.

scenario:flasksimple-appsec-get

• 🟩 max_rss_usage [-881.168KB; -724.873KB] or [-2.576%; -2.119%]

scenario:flasksimple-appsec-post

• 🟩 max_rss_usage [-891.825KB; -729.372KB] or [-2.612%; -2.136%]

scenario:otelspan-add-metrics

• 🟥 max_rss_usage [+1.115MB; +1.251MB] or [+2.735%; +3.069%]

scenario:otelspan-add-tags

• 🟥 max_rss_usage [+1.184MB; +1.346MB] or [+2.897%; +3.296%]

scenario:otelspan-start-finish

• 🟩 max_rss_usage [-855.254KB; -711.875KB] or [-2.899%; -2.413%]

scenario:samplingrules-low_match

• 🟩 max_rss_usage [-838.336KB; -726.745KB] or [-2.943%; -2.552%]

scenario:sethttpmeta-obfuscation-disabled

• 🟥 max_rss_usage [+598.045KB; +756.911KB] or [+2.134%; +2.701%]

scenario:sethttpmeta-obfuscation-regular-case-explicit-query

• 🟥 max_rss_usage [+572.228KB; +724.156KB] or [+2.030%; +2.569%]

scenario:sethttpmeta-obfuscation-regular-case-implicit-query

• 🟩 max_rss_usage [-1.302MB; -1.156MB] or [-4.505%; -3.998%]

scenario:sethttpmeta-useragentvariant_not_exists_2

• 🟥 max_rss_usage [+874.178KB; +1009.572KB] or [+3.160%; +3.649%]

scenario:span-start-finish

• 🟩 max_rss_usage [-912.832KB; -750.964KB] or [-3.202%; -2.634%]

scenario:span-start-finish-telemetry

• 🟥 max_rss_usage [+576.581KB; +717.755KB] or [+2.034%; +2.532%]

scenario:span-start-finish-traceid128

• 🟥 max_rss_usage [+608.879KB; +762.462KB] or [+2.193%; +2.746%]

[emmettbutler]

@Yun-Kim how would you like me to approach this review? Since the base isn't 1.x I'm not entirely sure what standards to apply. Maybe I should wait until the base is 1.x to do a review?

[Yun-Kim]

@emmettbutler I've cleaned up the PR description to be more clear on what's being changed, and even though I technically don't need an approval to merge into the base branch 2.x-dev (our current working branch before we cut 2.x), I'd still love a review!

Ideally #6612 gets merged into this first before we merge this into 2.x-dev, but I've separated this from #6612 for easier review.

[majorgreys]

quick check