build(deps): bump proc-macro2 from 1.0.76 to 1.0.78 (paritytech#1388)

Bumps [proc-macro2](https://github.com/dtolnay/proc-macro2) from 1.0.76 to 1.0.78.
- [Release notes](https://github.com/dtolnay/proc-macro2/releases)
- [Commits](dtolnay/proc-macro2@1.0.76...1.0.78)

---
updated-dependencies:
- dependency-name: proc-macro2
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Cargo.toml

@@ -75,7 +75,7 @@ jsonrpsee = { version = "0.21" }
 pretty_assertions = "1.4.0"
 primitive-types = { version = "0.12.2", default-features = false, features = ["codec", "scale-info", "serde"] }
 proc-macro-error = "1.0.4"
-proc-macro2 = "1.0.70"
+proc-macro2 = "1.0.78"
 quote = "1.0.35"
 regex = "1.10.2"
 scale-info = "2.10.0"