gnu: go-github-com-xtaci-lossyconn: Disable tests.

As seen in <https://ci.guix.gnu.org/build/9029279/log/raw>, goroutine
fail when number of threads are more than 16.

* gnu/packages/golang-web.scm (go-github-com-xtaci-lossyconn)
[arguments] <tests?>: Disable them.
<parallel-tests?>: Likewise.

Change-Id: Ic66c0ef4659e2351786f4b97df045544cd0d22f1

gnu/packages/golang-web.scm

@@ -8358,6 +8358,10 @@ version with various improvements
     (build-system go-build-system)
     (arguments
      (list
+      ;; XXX: In CI with 16+ threads goroutines fail. Figure out how to detect
+      ;; CI enviroment.
+      #:tests? #f
+      #:parallel-tests? #f
       #:import-path "github.com/xtaci/lossyconn"))
     (home-page "https://github.com/xtaci/lossyconn")
     (synopsis "Lossy connection simulator")