ApiKeyValueMapDownload Command (#3245)

* ApiKeyValueMapDownload Command

* CodeReview Fixes

documentation/docs/steps/apiKeyValueMapDownload.md

@@ -0,0 +1,30 @@
+# ${docGenStepName}
+
+## ${docGenDescription}
+
+## Prerequisites
+
+## ${docGenParameters}
+
+## ${docGenConfiguration}
+
+## ${docJenkinsPluginDependencies}
+
+## Example
+
+Example configuration for the use in a `Jenkinsfile`.
+
+```groovy
+apiKeyValueMapDownload script: this
+```
+
+Example for the use in a YAML configuration file (such as `.pipeline/config.yaml`).
+
+```yaml
+steps:
+  <...>
+  apiKeyValueMapDownload:
+    apimApiServiceKeyCredentialsId: 'MY_API_SERVICE_KEY'
+    apiProxyName: 'MY_API_KEY_VALUE_MAP_NAME'
+    downloadPath: MY_API_KEY_VALUE_MAP_CSV_FILE_DOWNLOAD_PATH
+```