ext/filter: make sure filter.so is loaded when invoking PHP inside a phpt test

The test-suite uses `-d extension_dir=...` & `-d extension=...` to make sure the
correct extension is loaded. This change also introduces this behavior for the
new regression tests.

This in fact bit the nixpkgs build while updating to the earlier-released
patches since we have split off most extension builds from core.

Author: Ma27

ext/filter/tests/oom_filter_default_encoded.phpt

@@ -26,6 +26,8 @@ function oom_post_encoded(string $body, string $script): void
             '-d', 'html_errors=0',
             '-d', 'filter.default=encoded',
             '-d', 'filter.default_flags=0',
+            '-d', sprintf("extension_dir=%s", ini_get('extension_dir')),
+            '-d', 'extension=filter.so',
             /* the conversion is what is under test, not the deprecation */
             '-d', 'error_reporting=' . (E_ALL & ~E_DEPRECATED),
         ],

ext/filter/tests/oom_filter_input.phpt

@@ -23,7 +23,13 @@ $body = "--$boundary\r\nContent-Disposition: form-data; name=\"k\"\r\n\r\n"
       . "\r\n--$boundary--\r\n";
 
 $p = proc_open(
-    [getenv('TEST_PHP_CGI_EXECUTABLE'), '-n', '-d', 'memory_limit=12M', '-d', 'html_errors=0'],
+    [
+        getenv('TEST_PHP_CGI_EXECUTABLE'), '-n',
+        '-d', 'memory_limit=12M',
+        '-d', 'html_errors=0',
+        '-d', sprintf("extension_dir=%s", ini_get('extension_dir')),
+        '-d', 'extension=filter.so',
+    ],
     [0 => ['pipe', 'r'], 1 => ['pipe', 'w'], 2 => ['pipe', 'w']],
     $pipes,
     null,

ext/filter/tests/oom_filter_input_array.phpt

@@ -23,7 +23,13 @@ $body = "--$boundary\r\nContent-Disposition: form-data; name=\"k\"\r\n\r\n"
       . "\r\n--$boundary--\r\n";
 
 $p = proc_open(
-    [getenv('TEST_PHP_CGI_EXECUTABLE'), '-n', '-d', 'memory_limit=12M', '-d', 'html_errors=0'],
+    [
+        getenv('TEST_PHP_CGI_EXECUTABLE'), '-n',
+        '-d', 'memory_limit=12M',
+        '-d', 'html_errors=0',
+        '-d', sprintf("extension_dir=%s", ini_get('extension_dir')),
+        '-d', 'extension=filter.so',
+    ],
     [0 => ['pipe', 'r'], 1 => ['pipe', 'w'], 2 => ['pipe', 'w']],
     $pipes,
     null,