MDL-65292 style: Fix all function declarations white space

This has been generated running the following Sniffs, all
them part of the Moodle's CodeSniffer standard:
- PSR12.Functions.ReturnTypeDeclaration
- PSR12.Functions.NullableTypeDeclaration
- moodle.Methods.MethodDeclarationSpacing
- Squiz.Whitespace.ScopeKeywordSpacing

All them are, exclusively, about correct spacing, so the changes
are, all them, only white space changes.

Only exceptions to the above are 3 changes what were setting the
return type in a new line, and, when that happens, the closing
parenthesis (bracket) has to go to the same line than the colon.

competency/classes/privacy/provider.php

@@ -69,7 +69,7 @@ class provider implements
      * @param collection $collection The initialised collection to add items to.
      * @return collection A listing of user data stored through this system.
      */
-    public static function get_metadata(collection $collection) : collection {
+    public static function get_metadata(collection $collection): collection {
 
         // Tables not related to users aside from the editing information.
         $collection->add_database_table('competency', [
@@ -215,7 +215,7 @@ class provider implements
      * @param int $userid The user to search.
      * @return contextlist $contextlist The contextlist containing the list of contexts used in this plugin.
      */
-    public static function get_contexts_for_userid(int $userid) : contextlist {
+    public static function get_contexts_for_userid(int $userid): contextlist {
         global $DB;
         $contextlist = new \core_privacy\local\request\contextlist();