Prepare 1.2

[CaselIT]

• modernize setup: https://gerrit.sqlalchemy.org/c/sqlalchemy/mako/+/3078
• drop py2: https://gerrit.sqlalchemy.org/c/sqlalchemy/mako/+/3078
• github workflow: https://gerrit.sqlalchemy.org/c/sqlalchemy/mako/+/3078
• improve code: see #335
• update black : redo #312
• remove pkg_resource usage #347
• #351
• #352

[jvanasco]

For the "update black" item, I suggest re-doing PR #312, which standardizes the black integration into the same config as other sqlalchemy projects:

• migrate black config to pyproject.toml
• update black version

If you have time, I would also copy/paste this:

• update README to showcase code-of-conduct and development links

[bourke]

Implemented in c8140243