AbstractWithPreferencesTest: Disable update checks

This prevents the Arduino instance in tests from checking for updates. I
have not seen any problems resulting from this, but disabling network
requests is generally a good idea in tests (to prevent external factors
from influencing the test results).

In addition to update checks, there is also the CloudBoardResolver that
could do network requests, but there does not seem to be a preference
for disabling that.

Author: matthijskooijman

Diff for: app/test/processing/app/AbstractWithPreferencesTest.java

@@ -67,6 +67,8 @@ public void init() throws Exception {
     PreferencesData.set("settings.path", settingsDir.toString());
     // Do not read or write the default ~/Arduino sketchbook
     PreferencesData.set("sketchbook.path", sketchbookDir.toString());
+    // Do not perform any update checks
+    PreferencesData.set("update.check", sketchbookDir.toString());
     // Write the defaults, with these changes to file. This allows them
     // to be reloaded when creating a Base instance (see getBaseArgs()
     // below).