fix: Update Beta build configuration

The Beta build configuration was stale, which indirectly resulted in
build failures (due to a code fence bug). The beta config should match
the `main` config with respect to feature support.

builds.yml

@@ -39,11 +39,18 @@ buildTypes:
   beta:
     features:
       - build-beta
+      - snaps
+      - keyring-snaps
+      - blockaid
     env:
       - INFURA_BETA_PROJECT_ID
       - SEGMENT_BETA_WRITE_KEY
       - INFURA_ENV_KEY_REF: INFURA_BETA_PROJECT_ID
       - SEGMENT_WRITE_KEY_REF: SEGMENT_BETA_WRITE_KEY
+      - ALLOW_LOCAL_SNAPS: false
+      - REQUIRE_SNAPS_ALLOWLIST: true
+      - IFRAME_EXECUTION_ENVIRONMENT_URL: https://execution.metamask.io/iframe/6.4.0/index.html
+      - ACCOUNT_SNAPS_DIRECTORY_URL: https://snaps.metamask.io/account-management
     # Modifies how the version is displayed.
     # eg. instead of 10.25.0 -> 10.25.0-beta.2
     isPrerelease: true