fix: don't run Jenkins on doc/ branches and PRs

Jenkinsfile

@@ -1,3 +1,5 @@
+def skipRemainingStages = false
+
 pipeline {
   agent { label 'lagoon' }
   environment {
@@ -20,6 +22,20 @@ pipeline {
         sh 'env'
       }
     }
+    stage ('skip on docs commit') {
+      when {
+        anyOf {
+          changeRequest branch: 'docs\\/.*', comparator: 'REGEXP'
+          branch pattern: "docs\\/.*", comparator: "REGEXP"
+        }
+      }
+      steps {
+        script {
+          skipRemainingStages = true
+          echo "Docs only update, no build needed."
+        }
+      }
+    }
     // in order to have the newest images from upstream (with all the security
     // updates) we clean our local docker cache on tag deployments
     // we don't do this all the time to still profit from image layer caching
@@ -28,12 +44,20 @@ pipeline {
     stage ('clean docker image cache') {
       when {
         buildingTag()
+        expression {
+            !skipRemainingStages
+        }
       }
       steps {
         sh script: "docker image prune -af", label: "Pruning images"
       }
     }
     stage ('build and push images') {
+      when {
+        expression {
+            !skipRemainingStages
+        }
+      }
       environment {
         PASSWORD = credentials('amazeeiojenkins-dockerhub-password')
       }
@@ -46,11 +70,21 @@ pipeline {
       }
     }
     stage ('show trivy scan results') {
+      when {
+        expression {
+            !skipRemainingStages
+        }
+      }
       steps {
         sh script: "cat scan.txt", label: "Display scan results"
       }
     }
     stage ('setup test cluster') {
+      when {
+        expression {
+            !skipRemainingStages
+        }
+      }
       parallel {
         stage ('0: setup test cluster') {
           steps {
@@ -72,6 +106,11 @@ pipeline {
       }
     }
     stage ('run first test suite') {
+      when {
+        expression {
+            !skipRemainingStages
+        }
+      }
       parallel {
         stage ('1: run first test suite') {
           steps {
@@ -106,6 +145,11 @@ pipeline {
       }
     }
     stage ('run second test suite') {
+      when {
+        expression {
+            !skipRemainingStages
+        }
+      }
       parallel {
         stage ('2: run second test suite') {
           steps {
@@ -126,6 +170,11 @@ pipeline {
       }
     }
     stage ('run third test suite') {
+      when {
+        expression {
+            !skipRemainingStages
+        }
+      }
       parallel {
         stage ('3: run third test suite') {
           steps {
@@ -146,11 +195,14 @@ pipeline {
       }
     }
     stage ('push images to testlagoon/* with :latest tag') {
-      when {
+       when {
         branch 'main'
         not {
           environment name: 'SKIP_IMAGE_PUBLISH', value: 'true'
         }
+        expression {
+            !skipRemainingStages
+        }
       }
       environment {
         PASSWORD = credentials('amazeeiojenkins-dockerhub-password')
@@ -166,6 +218,9 @@ pipeline {
         not {
           environment name: 'SKIP_IMAGE_PUBLISH', value: 'true'
         }
+        expression {
+            !skipRemainingStages
+        }
       }
       environment {
         TOKEN = credentials('git-amazeeio-helmfile-ci-trigger')
@@ -180,6 +235,9 @@ pipeline {
         not {
           environment name: 'SKIP_IMAGE_PUBLISH', value: 'true'
         }
+        expression {
+            !skipRemainingStages
+        }
       }
       environment {
         PASSWORD = credentials('amazeeiojenkins-dockerhub-password')
@@ -195,6 +253,9 @@ pipeline {
           branch 'testing/scans'
           buildingTag()
         }
+        expression {
+            !skipRemainingStages
+        }
       }
       steps {
         sh script: 'make scan-images', label: "perform scan routines"