fix: skip the invalid fd IPv6 bind test in DevContainer environments

The "invalid fd IPv6 bind address" table entry binds [::1]:0 but was
missing ipv6: true, so skipDevContainer never ran for it and the test
failed with "bind: cannot assign requested address" under DEVCONTAINER=1
on hosts without IPv6. Mark it ipv6 like its sibling "valid fd IPv6 bind
address" entry so the guard skips it.

Signed-off-by: Mateen Anjum <mateenali66@gmail.com>

CHANGELOG.md

@@ -8,6 +8,8 @@
 
 ## Changes since v7.15.2
 
+- [#3442](https://github.com/oauth2-proxy/oauth2-proxy/pull/3442) fix: skip the invalid fd IPv6 bind test in DevContainer environments (@mateenali66)
+
 # V7.15.2
 
 ## Release Highlights

pkg/proxyhttp/server_test.go

@@ -394,6 +394,7 @@ var _ = Describe("Server", func() {
 				expectHTTPListener: true,
 				expectTLSListener:  false,
 				fdAddr:             "[::1]:0",
+				ipv6:               true,
 			}),
 			Entry("with an ipv6 valid http bind address", &newServerTableInput{
 				opts: Opts{