build: fix var [build]

Author: forevanyeung

.github/workflows/build.yaml

@@ -74,7 +74,7 @@ jobs:
         run: |
           # create variables
           CERTIFICATE_PATH=$RUNNER_TEMP/build_certificate.p12
-          KEYCHAIN_PASSWORD: $(openssl rand -base64 32)
+          KEYCHAIN_PASSWORD=$(openssl rand -base64 32)
           KEYCHAIN_PATH=$RUNNER_TEMP/app-signing.keychain-db
 
           # import certificate and provisioning profile from secrets