Fix cmd/config windows issues

kyaml/fn/runtime/container/container.go

@@ -194,9 +194,12 @@ func (c *Filter) getCommand() (string, []string) {
 
 	// export the local environment vars to the container
 	for _, pair := range os.Environ() {
-		args = append(args, "-e", strings.Split(pair, "=")[0])
+		items := strings.Split(pair, "=")
+		if items[0] == "" || items[1] == "" {
+			continue
+		}
+		args = append(args, "-e", items[0])
 	}
 	a := append(args, c.Image)
-
 	return "docker", a
 }

kyaml/fn/runtime/container/container_test.go

@@ -103,7 +103,11 @@ metadata:
 			// configure expected env
 			for _, e := range os.Environ() {
 				// the process env
-				tt.expectedArgs = append(tt.expectedArgs, "-e", strings.Split(e, "=")[0])
+				parts := strings.Split(e, "=")
+				if parts[0] == "" || parts[1] == "" {
+					continue
+				}
+				tt.expectedArgs = append(tt.expectedArgs, "-e", parts[0])
 			}
 			tt.expectedArgs = append(tt.expectedArgs, tt.instance.Image)