chore(cargo): bump async-smtp from 0.9.0 to 0.9.1

Bumps [async-smtp](https://github.com/async-email/async-smtp) from 0.9.0 to 0.9.1.
- [Commits](https://github.com/async-email/async-smtp/compare/v0.9.0...v0.9.1)

---
updated-dependencies:
- dependency-name: async-smtp
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Cargo.lock

@@ -267,9 +267,9 @@ dependencies = [
 
 [[package]]
 name = "async-smtp"
-version = "0.9.0"
+version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8709c0d4432be428a88a06746689a9cb543e8e27ef7f61ca4d0455003a3d8c5b"
+checksum = "928ea96f04e1260036cb01f82c1e5dc7c3b478e7b9463c87712297784ce3cdc6"
 dependencies = [
  "anyhow",
  "base64 0.13.1",