[lagobot] enable pipenv (#820)

## Summary

The pipenv stuff is slow, because it seems to not respect the nix
packages cache? Not fully sure. We should debug it.

But we can land it for now, since we are no longer running examples
tests on PRs. They will be run on `main` soon.

## How was it tested?

Author: savil

testscripts/testrunner/examplesrunner.go

@@ -44,12 +44,11 @@ func RunExamplesTestscripts(t *testing.T, examplesDir string) {
 		// TODO savil. Resolve these.
 		skipList := []string{
 
+			// pipenv: is enabled since it passes but it is slow, and we should examine why.
+
 			// drupal:
 			// https://gist.github.com/savil/9c67ffa50a2c51d118f3a4ce29ab920d
 			"drupal",
-
-			// pipenv takes too long: 350 seconds
-			"pipenv",
 		}
 		for _, toSkip := range skipList {
 			if strings.Contains(path, toSkip) {
@@ -58,7 +57,6 @@ func RunExamplesTestscripts(t *testing.T, examplesDir string) {
 			}
 		}
 
-		// TODO run in parallel
 		t.Logf("running testscript for example: %s\n", path)
 		runSingleExampleTestscript(t, examplesDir, path)
 		return nil