Fix: Make all 'relative paths' absolute (#28196)

# Fix: Make all 'relative paths' absolute

The phpcs ruleset xml file's relative exclude patterns are relative to
the filename(s) provided on the command line.
Hence with partial verifications, the path exclusion does not function
as we would like.
Removing the relative-path attribute from the patterns the exclusion
works.
At the same time, the patterns were optimized and a comment was added.

dev/setup/codesniffer/ruleset.xml

@@ -5,20 +5,20 @@
 	<arg name="tab-width" value="4"/>
 	<arg name="extensions" value="php" />
 
-	<exclude-pattern type="relative">build/html</exclude-pattern>
-	<exclude-pattern type="relative">build/aps</exclude-pattern>
-	<exclude-pattern type="relative">dev/tools/test/namespacemig</exclude-pattern>
-	<!-- <exclude-pattern type="relative">dev/initdata/dbf/includes</exclude-pattern> -->
-	<exclude-pattern type="relative">documents</exclude-pattern>
-	<exclude-pattern type="relative">htdocs/core/class/lessc.class.php</exclude-pattern>
-	<exclude-pattern type="relative">htdocs/custom</exclude-pattern>
-	<exclude-pattern type="relative">htdocs/includes</exclude-pattern>
-	<exclude-pattern type="relative">htdocs/install/doctemplates/websites</exclude-pattern>
-	<exclude-pattern type="relative">htdocs/conf.php</exclude-pattern>
-	<exclude-pattern type="relative">*/nltechno*</exclude-pattern>
-	<exclude-pattern type="relative">source</exclude-pattern>
-	<exclude-pattern type="relative">.git</exclude-pattern>
-	<exclude-pattern type="relative">.cache</exclude-pattern>
+	<!-- info: '*' is replaced with '.*', so better use '+' in some cases -->
+	<!-- info: 'relative' paths are relative to the examined file, so not ok. -->
+	<exclude-pattern>/build/(html|aps)/</exclude-pattern>
+	<exclude-pattern>/dev/tools/test/namespacemig/</exclude-pattern>
+	<!-- <exclude-pattern>dev/initdata/dbf/includes</exclude-pattern> -->
+	<exclude-pattern>/documents/</exclude-pattern>
+	<exclude-pattern>/htdocs/core/class/lessc\.class\.php</exclude-pattern>
+	<exclude-pattern>/htdocs/(custom|includes)/</exclude-pattern>
+	<exclude-pattern>/htdocs/install/doctemplates/websites</exclude-pattern>
+	<exclude-pattern>/htdocs/([^/]+/)?conf\.php</exclude-pattern>
+	<exclude-pattern>*/nltechno*</exclude-pattern>
+	<exclude-pattern>/source/</exclude-pattern>
+	<exclude-pattern>/\.git/</exclude-pattern>
+	<exclude-pattern>/\.cache/</exclude-pattern>
 
 	<!-- List of all tests -->