Build/Test Tools: Reclassify json2php as a devDependency.

This dependency is responsible for transforming some JSON files to PHP ones. But since this is not included in the distributed software, it should not be specified as a `dependency`.

Props nimeshatxecurify, royhridoy, phpbits, dilip2615, noruzzaman.
Fixes #64221.

git-svn-id: https://develop.svn.wordpress.org/trunk@62061 602fd350-edb4-49c9-b593-d223f7449a82

Author: desrosj

package-lock.json

@@ -65,6 +65,7 @@
 		"grunt-sass": "~4.1.0",
 		"grunt-webpack": "7.0.1",
 		"install-changed": "1.1.0",
+		"json2php": "0.0.12",
 		"postcss": "8.5.8",
 		"prettier": "npm:wp-prettier@3.0.3",
 		"qunit": "~2.25.0",
@@ -96,7 +97,6 @@
 		"jquery-color": "3.0.0",
 		"jquery-form": "4.3.0",
 		"jquery-hoverintent": "1.10.2",
-		"json2php": "0.0.12",
 		"jsonlint": "1.6.3",
 		"lodash": "4.17.23",
 		"masonry-layout": "4.2.2",