Fix Redirector config escaped strings

When printing out the configuration JSON, the Redirector extension
expects regex escapes to be escaped, themselves. So `\` becomes `\\`.
However, Crystal treats these as escaped character also, and each `\`
must additionally be escaped, so a single slash becomes `\\\\`

CHANGELOG

@@ -1,3 +1,7 @@
+2022-07-19
+
+* Fix downloadable config file for Redirector extension
+
 2022-07-17
 
 * Fix source code link

src/actions/redirection_config/index.cr

@@ -15,6 +15,7 @@ class RedirectionConfig::Index < Lucky::Action
   end
 
   private def config_json
+    double_escaped_pattern = "^https?://(?:.*\\\\.)*(?<!(link\\\\.|cdn\\\\-images\\\\-\\\\d+\\\\.))medium\\\\.com(/.*)?$"
     <<-JSON
     {
       "createdBy": "Redirector v3.5.3",
@@ -25,7 +26,7 @@ class RedirectionConfig::Index < Lucky::Action
           "exampleUrl": "https://medium.com/@user/post-123456abcdef",
           "exampleResult": "https://#{app_domain}/@user/post-123456abcdef",
           "error": null,
-            "includePattern": "^https?://(?:.*\\.)*(?<!(link\\.|cdn\\-images\\-\\d+\\.))medium\\.com(/.*)?$",
+          "includePattern": "#{double_escaped_pattern}",
           "excludePattern": "",
           "patternDesc": "",
           "redirectUrl": "https://#{app_domain}$2",

src/version.cr

@@ -1,3 +1,3 @@
 module Scribe
-  VERSION = "2022-07-17"
+  VERSION = "2022-07-19"
 end