Roll bots to Xcode 12 beta 2

Bots rolled with the following script:
git grep -l '12a6159' | xargs sed -i '' -e 's/12a6159/12a6163b/g'

to update:
infra/config/lib/builders.star
infra/config/subprojects/chromium/master-only/ci.star
testing/buildbot/mixins.pyl
testing/buildbot/waterfalls.pyl

then configs were generated with:
./infra/config/main.star
./testing/buildbot/generate_buildbot_json.py

CIPD packages:
  infra_internal/ios/xcode/mac  12a6163b
  infra_internal/ios/xcode/ios  12a6163b

Bug: 1102933
Change-Id: I647e328ed6e8b0b7160a930eb97fb98f400944b6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2285387
Auto-Submit: Mike Dougherty <michaeldo@chromium.org>
Commit-Queue: Stephen Martinis <martiniss@chromium.org>
Reviewed-by: Stephen Martinis <martiniss@chromium.org>
Cr-Commit-Position: refs/heads/master@{#786895}

infra/config/generated/cr-buildbucket.cfg

@@ -10079,11 +10079,11 @@ buckets {
         cipd_version: "refs/heads/master"
         cmd: "recipes"
       }
-      properties: "{\"$build/goma\":{\"rpc_extra_params\":\"?prod\",\"server_host\":\"goma.chromium.org\"},\"$kitchen\":{\"devshell\":true,\"git_auth\":true},\"mastername\":\"chromium.fyi\",\"recipe\":\"chromium\",\"xcode_build_version\":\"12a6159\"}"
+      properties: "{\"$build/goma\":{\"rpc_extra_params\":\"?prod\",\"server_host\":\"goma.chromium.org\"},\"$kitchen\":{\"devshell\":true,\"git_auth\":true},\"mastername\":\"chromium.fyi\",\"recipe\":\"chromium\",\"xcode_build_version\":\"12a6163b\"}"
       execution_timeout_secs: 36000
       caches {
-        name: "xcode_ios_12a6159"
-        path: "xcode_ios_12a6159.app"
+        name: "xcode_ios_12a6163b"
+        path: "xcode_ios_12a6163b.app"
       }
       build_numbers: YES
       service_account: "chromium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"

infra/config/lib/builders.star

@@ -141,7 +141,7 @@ xcode_cache = struct(
    x11e503a_xct12b1 = xcode_enum('xcode_ios_11e503a_xct12b1', 'xcode_ios_11e503a_xct12b1.app'),
    x11n700h = xcode_enum('xcode_ios_11n700h', 'xcode_ios_11n700h.app'),
    # xcode12
-   x12a6159 = xcode_enum('xcode_ios_12a6159', 'xcode_ios_12a6159.app'),
+   x12a6163b = xcode_enum('xcode_ios_12a6163b', 'xcode_ios_12a6163b.app'),
 )
 
 

infra/config/subprojects/chromium/master-only/ci.star

@@ -1832,11 +1832,11 @@ ci.fyi_ios_builder(
         category = 'iOS|iOS14',
         short_name = 'sdk14',
     ),
-    caches = [xcode_cache.x12a6159],
+    caches = [xcode_cache.x12a6163b],
     executable = 'recipe:chromium',
     os = os.MAC_10_15,
     properties = {
-        'xcode_build_version': '12a6159'
+        'xcode_build_version': '12a6163b'
     }
 )
 

testing/buildbot/mixins.pyl

@@ -932,17 +932,17 @@
     },
   },
   # xcode 12
-  'xcode_12a6159': {
+  'xcode_12a6163b': {
     '$mixin_append': {
       'args': [
         '--xcode-build-version',
-        '12a6159'
+        '12a6163b'
       ],
     },
     'swarming': {
       'named_caches': [
         {
-          'name': 'xcode_ios_12a6159',
+          'name': 'xcode_ios_12a6163b',
           'path': 'Xcode.app',
         },
       ],

testing/buildbot/waterfalls.pyl

@@ -2094,7 +2094,7 @@
           'mac_10.15',
           'mac_toolchain',
           'out_dir_arg',
-          'xcode_12a6159',
+          'xcode_12a6163b',
         ],
         'test_suites': {
           'isolated_scripts': 'ios14_beta_simulator_tests'
@@ -2110,7 +2110,7 @@
           'mac_10.15',
           'mac_toolchain',
           'out_dir_arg',
-          'xcode_12a6159',
+          'xcode_12a6163b',
         ],
         'test_suites': {
           'isolated_scripts': 'ios14_sdk_simulator_tests'