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.

lib/phpunit/classes/coverage_info.php

@@ -42,7 +42,7 @@ class phpunit_coverage_info {
      * @param   string  $plugindir The root of the plugin, relative to the dataroot.
      * @return  array
      */
-    final public function get_includelists(string $plugindir) : array {
+    final public function get_includelists(string $plugindir): array {
         $coverages = [];
 
         $includelistfolders = array_merge([
@@ -79,7 +79,7 @@ class phpunit_coverage_info {
      * @param   string  $plugindir The root of the plugin, relative to the dataroot.
      * @return  array
      */
-    final public function get_excludelists(string $plugindir) : array {
+    final public function get_excludelists(string $plugindir): array {
         $coverages = [];
 
         if (!empty($plugindir)) {