Update 70checkmarketplace.yml

Author: tomcat323

buildspec/release/70checkmarketplace.yml

@@ -38,7 +38,7 @@ phases:
             - |
                 if [ "$STAGE" != "prod" ]; then
                   echo "checkmarketplace: Non-production stage detected. Installing beta version "${beta_version}"."
-                  VERSION=beta_version
+                  VERSION=${beta_version#@}
                 else
                   beta_version=""
                 fi