add ubuntu focal builds

Jenkinsfile

@@ -329,6 +329,15 @@ def buildDebianNative() {
     }
     tasks << getTasks(ubuntu, ubuntuArchs, build)
     
+    def ubuntuFocal = ["ubuntu-focal"]
+    def ubuntuFocalArchs = []
+    if (params.BUILD_ALL == true) {
+        ubuntuFocalArchs = ["amd64", "armhf", "arm64", "ppc64le", "s390x"]
+    } else {
+        ubuntuFocalArchs = ["amd64"]
+    }
+    tasks << getTasks(ubuntuFocal, ubuntuFocalArchs, build)
+
     def kali = ["kali-rolling"]
     def kaliArchs = ["amd64"]
     tasks << getTasks(kali, kaliArchs, build)