fix(resources): replace regex guide (#58)

Author: Jiralite

resources/RESOURCES.md

@@ -23,7 +23,7 @@ see %USEFUL_SERVERS_CHANNEL% for invites to general JavaScript and programming s
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 ### Regular expressions:
 Trying to get some content out of a string but it's too complicated for slicing and dicing? Regular Expressions might be what you need:
-- [Regex Guide](https://blog.bitsrc.io/a-beginners-guide-to-regular-expressions-regex-in-javascript-9c58feb27eb4)
+- [Regex Guide](https://builtin.com/software-engineering-perspectives/javascript-regex)
 - Online Tester/Debugger: [regex101](https://regex101.com/) | [regexr](http://regexr.com/) | [debuggex](https://www.debuggex.com/)
 - Interactive Guide: [regexone](https://regexone.com/)
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