Install prdoc from Parity fork (#5625)

Prdoc is now published as a Parity fork under the
[`parity-prdoc`](https://crates.io/crates/parity-prdoc) crate after the
directions diverged from the ideas of the original creator (discussions
[here](https://github.com/paritytech/prdoc/pull/40) and
[here](https://github.com/paritytech/prdoc/issues/36)).
Now updating the install instructions here.

---------

Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

.github/workflows/check-prdoc.yml

@@ -6,7 +6,7 @@ on:
   merge_group:
 
 env:
-  IMAGE: docker.io/paritytech/prdoc:v0.0.8
+  IMAGE: docker.io/paritytech/prdoc:v0.1.1
   API_BASE: https://api.github.com/repos
   REPO: ${{ github.repository }}
   GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

docs/contributor/prdoc.md

@@ -14,7 +14,7 @@ the [CODEOWNERS](../../.github/CODEOWNERS) for advice.
 
 A `.prdoc` file is a YAML file with a defined structure (ie JSON Schema). Please follow these steps to generate one:
 
-1. Install the [`prdoc` CLI](https://github.com/paritytech/prdoc) by running `cargo install prdoc`.
+1. Install the [`prdoc` CLI](https://github.com/paritytech/prdoc) by running `cargo install parity-prdoc`.
 1. Open a Pull Request and get the PR number.
 1. Generate the file with `prdoc generate <PR_NUMBER>`. The output filename will be printed.
 1. Optional: Install the `prdoc/schema_user.json` schema in your editor, for example