Avoid timeouts in knapsack PRO

The way it's recommended since knapsack_pro version 2.3.0 [1].

[1] https://github.com/KnapsackPro/knapsack_pro-ruby/blob/master/CHANGELOG.md#230

bin/knapsack_pro_rspec

@@ -2,6 +2,7 @@
 if [ "$KNAPSACK_PRO_TEST_SUITE_TOKEN_RSPEC" = "" ]; then
   KNAPSACK_PRO_ENDPOINT=https://api-disabled-for-fork.knapsackpro.com \
     KNAPSACK_PRO_TEST_SUITE_TOKEN_RSPEC=disabled-for-fork \
+    KNAPSACK_PRO_MAX_REQUEST_RETRIES=0 \
     bundle exec rake knapsack_pro:rspec # use Regular Mode here always
 else
   # Queue Mode - dynamic tests allocation across CI nodes