gopls/internal/test: skip integration tests on linux-ppc64-power9osu

Tests are regularly timing out on this builder. Since it is not a first
class port, it's OK to skip these tests with -short.

Fixes golang/go#66748

Change-Id: I7fdf50db47b2e79fb87813ac98dea1d25e0d4453
Reviewed-on: https://go-review.googlesource.com/c/tools/+/577795
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Alan Donovan <adonovan@google.com>

gopls/internal/test/integration/runner.go

@@ -271,16 +271,17 @@ func (r *Runner) Run(t *testing.T, files string, test TestFunc, opts ...RunOptio
 // longBuilders maps builders that are skipped when -short is set to a
 // (possibly empty) justification.
 var longBuilders = map[string]string{
-	"openbsd-amd64-64":        "golang.org/issues/42789",
-	"openbsd-386-64":          "golang.org/issues/42789",
-	"openbsd-386-68":          "golang.org/issues/42789",
-	"openbsd-amd64-68":        "golang.org/issues/42789",
+	"openbsd-amd64-64":        "go.dev/issue/42789",
+	"openbsd-386-64":          "go.dev/issue/42789",
+	"openbsd-386-68":          "go.dev/issue/42789",
+	"openbsd-amd64-68":        "go.dev/issue/42789",
 	"darwin-amd64-10_12":      "",
 	"freebsd-amd64-race":      "",
 	"illumos-amd64":           "",
 	"netbsd-arm-bsiegert":     "",
 	"solaris-amd64-oraclerel": "",
 	"windows-arm-zx2c4":       "",
+	"linux-ppc64le-power9osu": "go.dev/issue/66748",
 }
 
 // TODO(rfindley): inline into Main.