Including pluginDir to linux/appimage/build.sh (#1850)

dist/linux/appimage/build.sh

@@ -41,6 +41,7 @@ ${JAVA_HOME}/bin/jpackage \
     --app-version "${VERSION}.${REVISION_NO}" \
     --java-options "-Dfile.encoding=\"utf-8\"" \
     --java-options "-Dcryptomator.logDir=\"~/.local/share/Cryptomator/logs\"" \
+    --java-options "-Dcryptomator.pluginDir=\"~/.local/share/Cryptomator/plugins\"" \
     --java-options "-Dcryptomator.settingsPath=\"~/.config/Cryptomator/settings.json:~/.Cryptomator/settings.json\"" \
     --java-options "-Dcryptomator.ipcSocketPath=\"~/.config/Cryptomator/ipc.socket\"" \
     --java-options "-Dcryptomator.mountPointsDir=\"~/.local/share/Cryptomator/mnt\"" \