Connection.set_charset(charset) was marked for future removal but did not emit a deprecation signal at call time. This change adds runtime deprecation signaling and updates release notes accordingly.

• Runtime deprecation behavior

  • Connection.set_charset(charset) now emits DeprecationWarning and continues delegating to set_character_set(charset) to preserve behavior.

• Focused deprecation coverage

  • Added a focused test in pymysql/tests/test_err.py asserting:
    • the warning category/message, and
    • delegation to set_character_set(...).

• Changelog update

  • Added an entry under v1.2.0 noting that Connection.set_charset(charset) now emits DeprecationWarning.

warnings.warn(
    "'set_charset' is deprecated, use 'set_character_set' instead",
    DeprecationWarning,
    2,
)
self.set_character_set(charset)