message: Update manifest.md
  Based on feedback, removed invalid value statement.
diff: @@ -119,7 +119,7 @@ brackets at the end of each author.
  <a id="the-edition-field-optional"></a>
  #### The `edition` field
  -The `edition` key is an optional key that affects which edition your package
  +The `edition` key is an optional key that affects which [Rust Edition] your package
  is compiled with. [`cargo new`] will generate a package with the `edition` key
  set to the latest edition. Setting the `edition` key in
  `[package]` will affect all targets/crates in the package, including test
  @@ -131,7 +131,7 @@ suites, benchmarks, binaries, examples, etc.
  edition = '2018'
  ```
  -If the `edition` key is not set, or the value is not a valid [Rust edition] in your `Cargo.toml`, Cargo will default to 2015.
  +If the `edition` key is not set in your `Cargo.toml`, Cargo will default to 2015.
  #### The `description` field
  