[PHP client] Fix README.md template for php (OpenAPITools#1540)

* Fix README.md template for php

* update php openapi3 samples

Author: okapon

modules/openapi-generator/src/main/resources/php/README.mustache

@@ -30,7 +30,7 @@ To install the bindings via [Composer](http://getcomposer.org/), add the followi
 {
   "repositories": [
     {
-      "type": "git",
+      "type": "vcs",
       "url": "https://github.com/{{#composerVendorName}}{{.}}{{/composerVendorName}}{{^composerVendorName}}{{gitUserId}}{{/composerVendorName}}/{{#composerProjectName}}{{.}}{{/composerProjectName}}{{^composerProjectName}}{{gitRepoId}}{{/composerProjectName}}.git"
     }
   ],

samples/client/petstore-security-test/php/OpenAPIClient-php/README.md

@@ -19,7 +19,7 @@ To install the bindings via [Composer](http://getcomposer.org/), add the followi
 {
   "repositories": [
     {
-      "type": "git",
+      "type": "vcs",
       "url": "https://github.com/GIT_USER_ID/GIT_REPO_ID.git"
     }
   ],

samples/client/petstore/php/OpenAPIClient-php/README.md

@@ -19,7 +19,7 @@ To install the bindings via [Composer](http://getcomposer.org/), add the followi
 {
   "repositories": [
     {
-      "type": "git",
+      "type": "vcs",
       "url": "https://github.com/GIT_USER_ID/GIT_REPO_ID.git"
     }
   ],

samples/openapi3/client/petstore/php/OpenAPIClient-php/README.md

@@ -19,7 +19,7 @@ To install the bindings via [Composer](http://getcomposer.org/), add the followi
 {
   "repositories": [
     {
-      "type": "git",
+      "type": "vcs",
       "url": "https://github.com/GIT_USER_ID/GIT_REPO_ID.git"
     }
   ],