build(deps): bump pyinstaller from 6.20.0 to 6.21.0

Bumps [pyinstaller](https://github.com/pyinstaller/pyinstaller) from 6.20.0 to 6.21.0.
- [Release notes](https://github.com/pyinstaller/pyinstaller/releases)
- [Changelog](https://github.com/pyinstaller/pyinstaller/blob/develop/doc/CHANGES.rst)
- [Commits](https://github.com/pyinstaller/pyinstaller/compare/v6.20.0...v6.21.0)

---
updated-dependencies:
- dependency-name: pyinstaller
  dependency-version: 6.21.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/create-release.yml

@@ -33,7 +33,7 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v7
+        uses: actions/checkout@v6
 
       - name: Set up Python
         uses: actions/setup-python@v6
@@ -228,7 +228,7 @@ jobs:
     if: success()
 
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@v6
       - uses: actions/download-artifact@v8
         with:
           path: artifacts

.github/workflows/dev.yml

@@ -38,7 +38,7 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v7
+        uses: actions/checkout@v6
 
       - name: Set up Python
         uses: actions/setup-python@v6
@@ -227,7 +227,7 @@ jobs:
     if: success()
 
     steps:
-      - uses: actions/checkout@v7
+      - uses: actions/checkout@v6
       - uses: actions/download-artifact@v8
         with:
           path: artifacts

.github/workflows/sync-readme-dependencies.yml

@@ -18,7 +18,7 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v7
+        uses: actions/checkout@v6
 
       - name: Set up Python
         uses: actions/setup-python@v6

.github/workflows/test.yml

@@ -28,7 +28,7 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v7
+        uses: actions/checkout@v6
 
       - name: Set up Python
         uses: actions/setup-python@v6

requirements.txt

@@ -2,7 +2,7 @@ requests==2.34.2
 PySide6-Essentials==6.11.1
 beautifulsoup4==4.14.3
 darkdetect==0.7.1
-pyinstaller==6.20.0
+pyinstaller==6.21.0
 PyQtDarkTheme-fork==2.3.6
 plyer==2.1.0
 psutil==7.2.2