opentelemetry-sdk: add log record limits environment variables

[herin049]

Description

Adds support for the OTEL_LOGRECORD_ATTRIBUTE_COUNT_LIMIT and OTEL_LOGRECORD_ATTRIBUTE_VALUE_LENGTH_LIMIT environment variables. (see Spec Compliance Matrix)

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?

uv run tox -e py314-test-opentelemetry-sdk

Does This PR Require a Contrib Repo Change?

• Yes. - Link to PR:
• No.

Checklist:

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

[ocelotl]

If this environment variable exists and is set to "", then self.max_log_record_attributes would be set to None, but the spec says this should be 128. Should this be 128 in the situation described before?

[herin049]

The default should only apply if you don't have the environment variable set at all (which is the current behavior). If you set OTEL_LOGRECORD_ATTRIBUTE_COUNT_LIMIT="" then I think the assumption is that the limit should effectively be infinite. This is the current behavior of all of the attribute limits from what I can tell.

[ocelotl]

Left a question regarding possible default values.