make sure extra plugin paths are enabled (#8390)

* fix: Make sure extra plugin_paths are not commented out.

* fix: Do not use "-e" as backup suffix.

debian/jitsi-meet-prosody.postinst

         # Component "focus.jitmeet.example.com" "client_proxy"
         #    target_address = "focus@auth.jitmeet.example.com"
         if grep -q "Component \"focus.$JVB_HOSTNAME\"" $PROSODY_HOST_CONFIG && ! grep "Component \"focus.$JVB_HOSTNAME\" \"client_proxy\"" $PROSODY_HOST_CONFIG ;then
-            sed -i -e "s/Component \"focus.$JVB_HOSTNAME\"/Component \"focus.$JVB_HOSTNAME\" \"client_proxy\"\n    target_address = \"$JICOFO_AUTH_USER@auth.$JVB_HOSTNAME\"/" $PROSODY_HOST_CONFIG
+            sed -i "s/Component \"focus.$JVB_HOSTNAME\"/Component \"focus.$JVB_HOSTNAME\" \"client_proxy\"\n    target_address = \"$JICOFO_AUTH_USER@auth.$JVB_HOSTNAME\"/g" $PROSODY_HOST_CONFIG
+            PROSODY_CONFIG_PRESENT="false"
+        fi
+
+        # Old versions of jitsi-meet-prosody come with the extra plugin path commented out (https://github.com/jitsi/jitsi-meet/commit/e11d4d3101e5228bf956a69a9e8da73d0aee7949)
+        # Make sure it is uncommented, as it contains required modules.
+        if grep -q '--plugin_paths = { "/usr/share/jitsi-meet/prosody-plugins/" }' ;then
+            sed -i 's#--plugin_paths = { "/usr/share/jitsi-meet/prosody-plugins/" }#plugin_paths = { "/usr/share/jitsi-meet/prosody-plugins/" }#g' $PROSODY_HOST_CONFIG
             PROSODY_CONFIG_PRESENT="false"
         fi