GH Actions: do not persist credentials

> By default, using `actions/checkout` causes a credential to be persisted in the checked-out repo's `.git/config`, so that subsequent `git` operations can be authenticated.
>
> Subsequent steps may accidentally publicly persist `.git/config`, e.g. by including it in a publicly accessible artifact via `actions/upload-artifact`.
>
> However, even without this, persisting the credential in the `.git/config` is non-ideal unless actually needed.
>
> **Remediation**
>
> Unless needed for `git` operations, `actions/checkout` should be used with `persist-credentials: false`.
>
> If the persisted credential is needed, it should be made explicit with `persist-credentials: true`.

This has now been addressed in all workflows.

Refs:
* https://unit42.paloaltonetworks.com/github-repo-artifacts-leak-tokens/
* https://docs.zizmor.sh/audits/#artipacked

Author: jrfnl

.github/workflows/basic-qa.yml

@@ -31,6 +31,8 @@ jobs:
     steps:
       - name: Checkout code
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+        with:
+          persist-credentials: false
 
       - name: Restore lychee cache
         uses: actions/cache@0400d5f644dc74513175e3cd8d07132dd4860809 # v4.2.4
@@ -58,6 +60,8 @@ jobs:
     steps:
       - name: Checkout code
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+        with:
+          persist-credentials: false
 
       - name: Spellcheck
         uses: streetsidesoftware/cspell-action@dcd03dc3e8a59ec2e360d0c62db517baa0b4bb6d # v7.2.0
@@ -81,6 +85,8 @@ jobs:
     steps:
       - name: Checkout code
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+        with:
+          persist-credentials: false
 
       - name: Set up problem matcher
         uses: lumaxis/shellcheck-problem-matchers@b02a1715a00c729b20eed3ebb7edf56fa9a433ba # v2.1.0

.github/workflows/label-new-prs.yml

@@ -39,6 +39,8 @@ jobs:
       # Checkout is needed to use the `use_local_config` option.
       - name: Checkout code
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+        with:
+          persist-credentials: false
 
       - name: Verify changes to the labeling logic
         uses: srvaroa/labeler@0a20eccb8c94a1ee0bed5f16859aece1c45c3e55 # v1.13.0

.github/workflows/publish-wiki.yml

@@ -44,6 +44,8 @@ jobs:
     steps:
       - name: Checkout code
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+        with:
+          persist-credentials: false
 
       - name: Install PHP
         uses: shivammathur/setup-php@ec406be512d7077f68eed36e63f4d91bc006edc4 # 2.35.4