Change rust-version to make lock file versioning work

Author: TedDriggs

Cargo.toml

@@ -11,7 +11,7 @@ implementing custom derives.
 license = "MIT"
 readme = "README.md"
 edition = "2021"
-rust-version = "1.56"
+rust-version = "1.56.0"
 exclude = ["/.travis.yml", "/publish.sh", "/.github/**"]
 
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