remove unnecessary context reference from trigger job

(cherry picked from commit 817fdf9b439e85c3ddfda126b3efb4e45c36006b)

Author: spalger

.ci/Jenkinsfile_baseline_trigger

@@ -21,7 +21,7 @@ withGithubCredentials {
 
       commits.take(MAXIMUM_COMMITS_TO_BUILD).each { commit ->
         catchErrors {
-          githubCommitStatus.create(commit, 'pending', 'Baseline started.', context = 'kibana-ci-baseline')
+          githubCommitStatus.create(commit, 'pending', 'Baseline started.', 'kibana-ci-baseline')
 
           build(
             propagate: false,

vars/githubCommitStatus.groovy

@@ -35,7 +35,12 @@ def onFinish() {
 // state: error|failure|pending|success
 def create(sha, state, description, context = 'kibana-ci') {
   withGithubCredentials {
-    return githubApi.post("repos/elastic/kibana/statuses/${sha}", [ state: state, description: description, context: context, target_url: env.BUILD_URL ])
+    return githubApi.post("repos/elastic/kibana/statuses/${sha}", [
+      state: state,
+      description: description,
+      context: context,
+      target_url: env.BUILD_URL
+    ])
   }
 }