feat(podman): add method to generate podman based docker image package

vars/gomplate.groovy

@@ -0,0 +1,46 @@
+void call(String sourceTemplate, String destFile, Map env = [:], Map options = [:]) {
+    String gomplateBin = getOrInstallGomplate(options)
+
+    sh """
+    ${exportEnvMap(env)}
+    ${gomplateBin} -f '${sourceTemplate}' > '${destFile}'
+    """
+}
+
+String exportEnvMap(Map env) {
+    String exports = ''
+
+    env.each { item ->
+        exports = """
+        ${exports}
+        export ${item.key}="${item.value}"
+        """
+    }
+
+    return exports
+}
+
+String getOrInstallGomplate(Map options = [:]) {
+    String installDir = options.get('installDir', '/usr/local/bin')
+    String version = options.get('version', '3.10.0')
+    Boolean forceDownload = options.get('forceDownload', false)
+    String downloadUrl = options.get('downloadUrl', "https://github.com/hairyhenderson/gomplate/releases/download/v${version}/gomplate_linux-amd64")
+
+    String gomplateBin = ''
+
+    lock("${env.NODE_NAME}:gomplate-install") {
+        gomplateBin = sh(returnStdout: true, script: 'which gomplate || exit 0').trim()
+
+        if (gomplateBin == '' || forceDownload) {
+            sh("""
+            mkdir -p '${installDir}'
+            curl -o '${installDir}/gomplate' -sSL '${downloadUrl}'
+            chmod +x '${installDir}/gomplate'
+            """)
+
+            gomplateBin = "${installDir}/gomplate"
+        }
+    }
+
+    return gomplateBin
+}