fix: use less strict validation for external URLs (#1104)

* fix: use less strict validation for external URLs

Default url validation from the Yup module doesn't allow URLs like "http://custom-host", while it is
a correct value for an external URL.

fix #1068

* fix: resolve GitHub CodeQL review

src/components/Settings/SonarrModal/index.tsx

@@ -145,7 +145,10 @@ const SonarrModal = ({ onClose, sonarr, onSave }: SonarrModalProps) => {
         )
       : Yup.number(),
     externalUrl: Yup.string()
-      .url(intl.formatMessage(messages.validationApplicationUrl))
+      .matches(
+        /^https?:\/\/(www\.)?[-a-zA-Z0-9@:%._+~#=]{1,256}(\.[a-zA-Z0-9()]{1,6}\b([-a-zA-Z0-9()@:%_+.~#?&/=]*))?$/i,
+        intl.formatMessage(messages.validationApplicationUrl)
+      )
       .test(
         'no-trailing-slash',
         intl.formatMessage(messages.validationApplicationUrlTrailingSlash),