Fix WORM and BROWSER status calculation (#6360)

One typo introduced in a recent commit miscalculates if worm and browser
are enabled or not. A simple test is also added to detect this issue
in the future if it ever happens again.

cmd/test-utils_test.go

@@ -434,6 +434,7 @@ func resetGlobalIsXL() {
 
 func resetGlobalIsEnvs() {
 	globalIsEnvCreds = false
+	globalIsEnvWORM = false
 	globalIsEnvBrowser = false
 	globalIsEnvRegion = false
 	globalIsStorageClass = false