Fix reflect crash on modules using glob imports (#1816)

This excludes glob imports when creating a module's mirror

pkl-core/src/test/files/LanguageSnippetTests/input/api/reflect6.pkl

@@ -0,0 +1,13 @@
+import "pkl:reflect"
+import* "../../input-helper/globtest/child/*.pkl" as globbed
+
+// regression test for VmTyped.getImports()
+// `member.isImport()` is true for glob imports too, so reflecting a module that
+// uses `import*` previously threw ClassCastException when casting the glob
+// import's body to ImportNode.
+// Glob imports resolve to a mapping rather than a module type, so they are
+// excluded from `imports` (which only reports regular imports).
+res = reflect.Module(module).imports
+
+// the glob import itself still works
+globbedKeys = globbed.keys.toListing()

pkl-core/src/test/files/LanguageSnippetTests/output/api/reflect6.pcf

@@ -0,0 +1,4 @@
+res = Map("reflect", "pkl:reflect")
+globbedKeys {
+  "../../input-helper/globtest/child/moduleC.pkl"
+}