[infra] Bumped shards on slow builders

Bug: chromium:1279426
Change-Id: Ia8ce4598da5f5f31fa282c9e7ff330b39caa68d2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3350451
Auto-Submit: Alexander Schulze <alexschulze@chromium.org>
Reviewed-by: Liviu Rau <liviurau@chromium.org>
Commit-Queue: Liviu Rau <liviurau@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78410}

infra/testing/PRESUBMIT.py

@@ -125,7 +125,7 @@ def _check_test(error_msg, test):
 
   # Limit shards to 14 to avoid erroneous resource exhaustion.
   errors += _check_int_range(
-      error_msg, test, 'shards', lower_bound=1, upper_bound=14)
+      error_msg, test, 'shards', lower_bound=1, upper_bound=20)
 
   variant = test.get('variant', 'default')
   if not variant or not isinstance(variant, basestring):

infra/testing/builders.pyl

@@ -1575,7 +1575,7 @@
       'priority': 35,
     },
     'tests': [
-      {'name': 'v8testing', 'shards': 14},
+      {'name': 'v8testing', 'shards': 20},
       {'name': 'v8testing', 'variant': 'future', 'shards': 4},
     ],
   },