chore(deps): update Qt6 and submodules to latest

* Upgrade Qt6 version in CI workflows for improved compatibility
  and access to latest features
* Update `gpgme`, `openssl`, and `qttranslations` submodules
  to latest commits for security, localization, and stability
* Ensures build and test environments remain current

Author: saturneric

.github/workflows/release.yml

@@ -112,7 +112,7 @@ jobs:
       - name: Install Qt6
         uses: jurplel/install-qt-action@v4
         with:
-          version: "6.8.3"
+          version: "6.9.3"
           cache: "true"
         if: runner.os == 'Linux' || runner.os == 'macOS'
 

.github/workflows/testing-nightly.yml

@@ -134,7 +134,7 @@ jobs:
       - name: Install Qt6
         uses: jurplel/install-qt-action@v4
         with:
-          version: "6.8.3"
+          version: "6.9.3"
           cache: "true"
         if: runner.os == 'Linux' || runner.os == 'macOS'