fix: lint and deploy jobs running via a webhook trigger

Author: phani-srikar

.codebuild/scripts/lint_pr.sh

@@ -1,6 +1,8 @@
 set -xeo pipefail
 # extract the PR number from the PR link
 PR_NUM=${CODEBUILD_WEBHOOK_TRIGGER##*/}
+PROJECT_USERNAME=aws-amplify
+REPO_NAME=amplify-codegen
 
 if [ -z "$PR_NUM" ]; then
   echo "Could not determine PR number. Cannot determine fork point for linting. Skipping linting."

.codebuild/scripts/publish.sh

@@ -1,5 +1,9 @@
 #!/bin/bash -e
 
+if [[ "$CODEBUILD_WEBHOOK_TRIGGER" == "pr/"* ]]; then
+  BRANCH_NAME=${CODEBUILD_WEBHOOK_BASE_REF##*/}
+fi
+
 if [ -z "$BRANCH_NAME" ]; then
   echo "BRANCH_NAME is missing"
   exit 1