fix(config): Mark three unused config.yml options as deprecated

[waterWang]

Description

Three options in config.yml are never read anywhere in the repository — not in Python, not in the React UI, not in the Helm chart, not in the docs:

config.yml	option	added	references outside config.yml
line 1140	[logging] color_log_error_keywords	2.10.0	0
line 1148	[logging] color_log_warning_keywords	2.10.0	0
line 2737	[scheduler] ignore_first_depends_on_past_by_default	2.3.0	0

None of the three carried version_deprecated or deprecation_reason, so they were presented as current settings in config.yml (which drives both the generated airflow.cfg and the configuration reference). Someone reading the docs sets one of these and nothing happens, with no warning.

Fix

Add version_deprecated: 3.4.0 and deprecation_reason: This parameter is no longer used. to all three options, following the existing pattern used by e.g. [traces] otel_debug_traces_on.

Closes #71259