Add third-party deps to .kde-ci.yml

The CI system already provides these so it doesn't have any effect there, but this allows to generate correct dependency data for kdesrc-build from .kde-ci.yml

.kde-ci.yml

@@ -15,6 +15,9 @@ Dependencies:
     'libraries/kquickimageeditor': '@stable'
     'frameworks/sonnet': '@stable'
     'libraries/kirigami-addons': '@latest'
+    'third-party/libquotient': '@latest'
+    'third-party/qtkeychain': '@latest'
+    'third-party/cmark': '@latest'
 - 'on': ['Windows', 'Linux', 'FreeBSD']
   'require':
     'frameworks/qqc2-desktop-style': '@stable'