PHPC-1504: Add PHP 7.4 to AppVeyor build matrix

This adds x64 and x86 with and without ZTS for PHP 7.4, and reduces PHP 7.3 to x64 with and without ZTS.

Author: jmikola

.appveyor.yml

@@ -13,26 +13,36 @@ environment:
   SDK_BRANCH: php-sdk-2.1.1
 
   matrix:
-    - PHP_REL: 7.3
+    - PHP_REL: 7.4
       ARCHITECTURE: x64
       ZTS_STATE: enable
       APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
       PHP_BUILD_CRT: vc15
-    - PHP_REL: 7.3
+    - PHP_REL: 7.4
       ARCHITECTURE: x64
       ZTS_STATE: disable
       APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
       PHP_BUILD_CRT: vc15
-    - PHP_REL: 7.3
+    - PHP_REL: 7.4
       ARCHITECTURE: x86
       ZTS_STATE: enable
       APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
       PHP_BUILD_CRT: vc15
-    - PHP_REL: 7.3
+    - PHP_REL: 7.4
       ARCHITECTURE: x86
       ZTS_STATE: disable
       APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
       PHP_BUILD_CRT: vc15
+    - PHP_REL: 7.3
+      ARCHITECTURE: x64
+      ZTS_STATE: enable
+      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
+      PHP_BUILD_CRT: vc15
+    - PHP_REL: 7.3
+      ARCHITECTURE: x64
+      ZTS_STATE: disable
+      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
+      PHP_BUILD_CRT: vc15
     - PHP_REL: 7.2
       ARCHITECTURE: x64
       ZTS_STATE: enable