Prepare 6.7.0 Release (#268)

* Update readme with 6.7 changelog

* Update phpstan neon for external libraries

* Build assets, documentation, and translations

* Update version to 6.7.0

* Update readme with date, stable and compatible

Author: cbravobernal

docs/bin/manifest.json

@@ -29,11 +29,6 @@
         "parent": null,
         "markdown_source": "https://github.com/wordpress/secure-custom-fields/blob/trunk/docs/welcome/index.md"
     },
-    "code-reference/abilities": {
-        "slug": "abilities",
-        "parent": "code-reference",
-        "markdown_source": "https://github.com/wordpress/secure-custom-fields/blob/trunk/docs/code-reference/abilities/index.md"
-    },
     "code-reference/acf-bidirectional-functions-file": {
         "slug": "acf-bidirectional-functions-file",
         "parent": "code-reference",
@@ -284,11 +279,6 @@
         "parent": "welcome",
         "markdown_source": "https://github.com/wordpress/secure-custom-fields/blob/trunk/docs/welcome/quick-start.md"
     },
-    "code-reference/abilities/class-scf-post-type-abilities-file": {
-        "slug": "class-scf-post-type-abilities-file",
-        "parent": "abilities",
-        "markdown_source": "https://github.com/wordpress/secure-custom-fields/blob/trunk/docs/code-reference/abilities/class-scf-post-type-abilities-file.md"
-    },
     "code-reference/admin/admin-commands-file": {
         "slug": "admin-commands-file",
         "parent": "admin",