chore: refactor regex for redundant pipe (#2)

### Description:
> since this part is enclosed in `[]`, the pipes aren't necessary.

_Originally posted by @rgmz in
gitleaks#1265 (comment)

### Checklist:

* [x] Does your PR pass tests?
* [x] Have you written new tests for your changes?
* [x] Have you lint your code locally prior to submission?

Original: gitleaks#1266

cmd/generate/config/rules/rule.go

@@ -18,16 +18,16 @@ const (
 	identifierCaseInsensitivePrefix = `(?i:`
 	identifierCaseInsensitiveSuffix = `)`
 	identifierPrefix                = `(?:`
-	identifierSuffix                = `)(?:[0-9a-z\-_\t .]{0,20})(?:[\s|']|[\s|"]){0,3}`
+	identifierSuffix                = `)(?:[0-9a-z\-_\t .]{0,20})(?:[\s'"]){0,3}`
 
 	// commonly used assignment operators or function call
 	operator = `(?:=|>|:{1,3}=|\|\|:|<=|=>|:|\?=)`
 
 	// boundaries for the secret
 	// \x60 = `
 	secretPrefixUnique = `\b(`
-	secretPrefix       = `(?:'|\"|\s|=|\x60){0,5}(`
-	secretSuffix       = `)(?:['|\"|\n|\r|\s|\x60|;|<]|$)`
+	secretPrefix       = `(?:['\"\s=\x60]){0,5}(`
+	secretSuffix       = `)(?:['\"\n\r\s\x60;<]|$)`
 )
 
 func generateSemiGenericRegex(identifiers []string, secretRegex string, isCaseInsensitive bool) *regexp.Regexp {