install swagger from source

First of all this removes the need for a network connection, second
renovate can update the version as it is tracked in go.mod.

However the real important part is that the binary downloads are
broken[1]. For some reason the swagger created with them does not
include all the type information for the examples. However when building
from source the same thing works fine.

[1] https://github.com/go-swagger/go-swagger/issues/2842

Signed-off-by: Paul Holzinger <pholzing@redhat.com>

test/tools/vendor/github.com/go-openapi/runtime/logger/logger.go

@@ -0,0 +1,20 @@
+package logger
+
+import "os"
+
+type Logger interface {
+	Printf(format string, args ...interface{})
+	Debugf(format string, args ...interface{})
+}
+
+func DebugEnabled() bool {
+	d := os.Getenv("SWAGGER_DEBUG")
+	if d != "" && d != "false" && d != "0" {
+		return true
+	}
+	d = os.Getenv("DEBUG")
+	if d != "" && d != "false" && d != "0" {
+		return true
+	}
+	return false
+}