move getACommonTld to the shared pack

javascript/ql/lib/semmle/javascript/Regexp.qll

@@ -999,11 +999,12 @@ predicate isInterpretedAsRegExp(DataFlow::Node source) {
 /**
  * Provides utility predicates related to regular expressions.
  */
-module RegExpPatterns {
+deprecated module RegExpPatterns {
   /**
    * Gets a pattern that matches common top-level domain names in lower case.
+   * DEPRECATED: use the similarly named predicate from `HostnameRegex` from the `regex` pack instead.
    */
-  string getACommonTld() {
+  deprecated string getACommonTld() {
     // according to ranking by http://google.com/search?q=site:.<<TLD>>
     result = "(?:com|org|edu|gov|uk|net|io)(?![a-z0-9])"
   }

javascript/ql/lib/semmle/javascript/security/regexp/HostnameRegexp.qll

@@ -12,8 +12,6 @@ private module Impl implements Shared::HostnameRegexpSig<TreeImpl> {
   class DataFlowNode = JS::DataFlow::Node;
 
   class RegExpPatternSource = RegExp::RegExpPatternSource;
-
-  string getACommonTld() { result = RegExp::RegExpPatterns::getACommonTld() }
 }
 
 import Shared::Make<TreeImpl, Impl>

javascript/ql/src/Security/CWE-020/IncompleteUrlSubstringSanitization.qll

@@ -31,7 +31,7 @@ query predicate problems(
   (
     // target contains a domain on a common TLD, and perhaps some other URL components
     target
-        .regexpMatch("(?i)([a-z]*:?//)?\\.?([a-z0-9-]+\\.)+" + RegExpPatterns::getACommonTld() +
+        .regexpMatch("(?i)([a-z]*:?//)?\\.?([a-z0-9-]+\\.)+" + HostnameRegexp::getACommonTld() +
             "(:[0-9]+)?/?")
     or
     // target is a HTTP URL to a domain on any TLD

javascript/ql/src/Security/CWE-020/IncompleteUrlSubstringSanitizationSpecific.qll

@@ -3,3 +3,5 @@ import semmle.javascript.dataflow.InferredTypes
 
 /** Holds if `node` may evaluate to `value` */
 predicate mayHaveStringValue(DataFlow::Node node, string value) { node.mayHaveStringValue(value) }
+
+import semmle.javascript.security.regexp.HostnameRegexp as HostnameRegexp