Dont throw a runtime exception

Signed-off-by: Mario Danic <mario@lovelyhq.com>

app/src/main/java/com/nextcloud/talk/utils/SecurityUtils.java

@@ -74,7 +74,7 @@ public class SecurityUtils {
         } catch (BadPaddingException | IllegalBlockSizeException | KeyStoreException |
                 CertificateException | UnrecoverableKeyException | IOException
                 | NoSuchPaddingException | NoSuchAlgorithmException | InvalidKeyException e) {
-            throw new RuntimeException(e);
+            return false;
         }
     }