[None][infra] update github token name (#8907)

Author: niukuo

jenkins/L0_MergeRequest.groovy

@@ -514,16 +514,17 @@ def getGithubMRChangedFile(pipeline, githubPrApiUrl, function, filePath="") {
     def result = null
     def pageId = 0
     withCredentials([
-        string(
-            credentialsId: 'github-token-trtllm-ci',
-            variable: 'GITHUB_API_TOKEN'
+        usernamePassword(
+            credentialsId: 'github-cred-trtllm-ci',
+            usernameVariable: 'NOT_USED_YET',
+            passwordVariable: 'GITHUB_API_TOKEN'
         ),
     ]) {
         while(true) {
             pageId += 1
             def rawDataJson = pipeline.sh(
                 script: """
-                    curl --header "Authorization: Bearer $GITHUB_API_TOKEN" \
+                    curl --header "Authorization: Bearer \${GITHUB_API_TOKEN}" \
                          --url "${githubPrApiUrl}/files?page=${pageId}&per_page=20"
                 """,
                 returnStdout: true