Feature request: Add support for locking actions that use YAML anchors #252

Current versions of actions-lock (as of v0.4.0) fail to detect and lock actions that use YAML anchors in the uses: field.

For example, the following configuration containing YAML anchors remains unhandled:

# `gh actions-lock` does not handle `uses:` that use YAML anchors
- name: Checkout
  uses: &checkout-uses actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
  with: &checkout-with
    token: ...
    persist-credentials: ...

# Run the same action again using the same version and the same parameters
- name: Checkout again
  uses: *checkout-uses
  with: *checkout-with

Proposed Feature

Implementation of YAML anchor parsing enables actions-lock to correctly detect and process these actions as lock targets.

The expected behavior involves processing such configurations as follows:

  - name: Checkout
-   uses: &checkout-uses actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+   uses: &checkout-uses actions/checkout@v7.0.1
    with: &checkout-with
      token: ...
      persist-credentials: ...

  - name: Checkout again
    uses: *checkout-uses
    with: *checkout-with