* fix(macros): smarter `.env` loading, caching, and invalidation
* feat(mysql): test `.env` loading in CI
* feat(postgres): test `.env` loading in CI
* feat(macros): allow `DATABASE_URL` to be empty
* fix(examples/postgres): make `cargo-sqlx` executable
* fix(examples/postgres): `cargo sqlx` invocation
* feat(examples/postgres): check offline prepare on more examples
* fix(examples/postgres): the name of this step
* fix(cli): don't suppress error from `dotenv()`
* fix(ci/examples/postgres): don't use heredoc in this step
* fix(ci/examples/postgres): multi-tenant
* fix(ci/examples/sqlite): test `.env` loading
* chore: add CHANGELOG entry
