Upgrade to mongoose 7 (#14971)

* remove some unused dependencies

* update mongoose version

* make common tests pass

* Make unit tests pass

* make api v3 integration tests pass

* fix lint issues

* fix issue with package-lock

* fix(lint): we don't need no .js

* fix(lint): update to latest config-habitrpg

* chore(npm): update package locks

* fix(test): replace deprecated fn

* chore(package): update eslint-habitrpg again

* fix(lint): server linting

* fix(lint): client linting

* fix(client): correct mangled common imports

* chore(npm): update package-locks

* fix(lint): punctuation, module

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Co-authored-by: SabreCat <sabrecat@gmail.com>
Co-authored-by: SabreCat <sabe@habitica.com>

website/server/libs/user/validation.js

@@ -32,7 +32,7 @@ function usernameIsForbidden (username) {
   return forbiddenWordsMatched.length > 0;
 }
 
-const invalidCharsRegex = new RegExp('[^a-z0-9_-]', 'i');
+const invalidCharsRegex = /[^a-z0-9_-]/i;
 function usernameContainsInvalidCharacters (username) {
   const match = username.match(invalidCharsRegex);
   return match !== null && match[0] !== null;