Auto merge of #14493 - fokinv:stopnotifications, r=jdm

Fixed some typos in stopNotifications test.

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We called the startNotifications() method instead of stopNotifications() in the tests. According to the specification this method should return `InvalidStateError` and not `NetworkError`, so we changed that as well.

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- [x] `./mach test-tidy` does not report any errors

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- [x] There are tests for these changes

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tests/wpt/mozilla/meta/mozilla/bluetooth/stopNotifications/disconnect-called-before.html.ini

@@ -0,0 +1,5 @@
+[disconnect-called-before.html]
+  type: testharness
+  [disconnect() called before stopNotifications. Reject with InvalidStateError.]
+    expected: FAIL
+

tests/wpt/mozilla/meta/mozilla/bluetooth/stopNotifications/disconnect-called-during.html.ini

@@ -1,5 +1,5 @@
 [disconnect-called-during.html]
   type: testharness
-  [disconnect() called during stopNotifications. Reject with NetworkError.]
+  [disconnect() called during stopNotifications. Reject with InvalidStateError.]
     expected: FAIL