Update terminology

[hugovk]

Fixes #1404.

Rename "blacklist" to "blocklist"

Except for opcache.blacklist_filename which is a PHP config: https://www.php.net/manual/en/opcache.configuration.php#ini.opcache.blacklist-filename

There was a PR (php/php-src#5685) to rename it to opcache.exclude_list_filename but they couldn't reach consensus.

Rename "whitelist" to "allowlist"

Except for phpunit.xml.dist which is PHPUnit config.

However, when only needing PHPUnit 9.3 the following change can be made (re: sebastianbergmann/phpunit#4288):

diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index 5439d0d..ee11909 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -22,12 +22,12 @@
     </testsuites>
 
     <filter>
-        <whitelist addUncoveredFilesFromWhitelist="true" processUncoveredFilesFromWhitelist="false">
+        <coverage includeUncoveredFiles="true" processUncoveredFiles="false">
             <file>./PHPCompatibility/Sniff.php</file>
             <file>./PHPCompatibility/AbstractInitialValueSniff.php</file>
             <directory>./PHPCompatibility/Sniffs/</directory>
             <directory>./PHPCompatibility/Helpers/</directory>
-        </whitelist>
+        </coverage>
     </filter>
 
     <logging>