chore: update readme files

Author: hawkeye64

app-extension/README.md

@@ -22,7 +22,7 @@ quasar ext add @quasar/qpdfviewer@next
 # Uninstall
 To remove this App Extension from your Quasar application, run the following (in your Quasar app folder):
 ```
-quasar ext remove @quasar/qpdfviewer@next
+quasar ext remove @quasar/qpdfviewer
 ```
 
 # Describe

docs/src/pages/all-about-qpdfviewer/installation-types.md

@@ -22,7 +22,7 @@ $ quasar ext add @quasar/qpdfviewer@next
 
 To remove as an App Extension from your Quasar application, run the following (in your Quasar app folder):
 ```
-$ quasar ext remove @quasar/qpdfviewer@next
+$ quasar ext remove @quasar/qpdfviewer
 ```
 
 ### Describe