cloud: validate that there are not positional arguments

flag.Parse() parses arguments after boolean flags as positional argument.
This produces unexpected behaviour like this:
```
> -a "true" -b "true"
a: false

> -a -b "true"
b: true
```

Change-Id: I0f8555fc45acf305a5efd365a6eae03eb8930942
Reviewed-on: https://review.monogon.dev/c/monogon/+/1798
Reviewed-by: Serge Bazanski <serge@monogon.tech>
Tested-by: Jenkins CI
diff --git a/cloud/apigw/BUILD.bazel b/cloud/apigw/BUILD.bazel
index c0488f1..ee3b409 100644
--- a/cloud/apigw/BUILD.bazel
+++ b/cloud/apigw/BUILD.bazel
@@ -7,7 +7,10 @@
     srcs = ["main.go"],
     importpath = "source.monogon.dev/cloud/apigw",
     visibility = ["//visibility:private"],
-    deps = ["//cloud/apigw/server"],
+    deps = [
+        "//cloud/apigw/server",
+        "@io_k8s_klog_v2//:klog",
+    ],
 )
 
 go_binary(