osbase: move test packages under osbase/test

The cmd, freeport and socksproxy packages are only used in tests, and
are also intended to be only used in tests. This change moves these
packages under osbase/test.

Change-Id: I8fe679945990c295bdf822abfce56c25233c4588
Reviewed-on: https://review.monogon.dev/c/monogon/+/4564
Reviewed-by: Tim Windelschmidt <tim@monogon.tech>
Tested-by: Jenkins CI
diff --git a/metropolis/test/nanoswitch/BUILD.bazel b/metropolis/test/nanoswitch/BUILD.bazel
index d7f9d12..9aff921 100644
--- a/metropolis/test/nanoswitch/BUILD.bazel
+++ b/metropolis/test/nanoswitch/BUILD.bazel
@@ -14,8 +14,8 @@
         "//metropolis/node/core/network/dhcp4c",
         "//metropolis/node/core/network/dhcp4c/callback",
         "//osbase/bringup",
-        "//osbase/socksproxy",
         "//osbase/supervisor",
+        "//osbase/test/socksproxy",
         "@com_github_google_nftables//:nftables",
         "@com_github_google_nftables//expr",
         "@com_github_insomniacslk_dhcp//dhcpv4",