Set PHP_VERSION expansion in test variants

Author: alcaeus

.evergreen/config/test-variants.yml

@@ -10,6 +10,7 @@ buildvariants:
     expansions:
       FETCH_BUILD_VARIANT: "build-debian11"
       FETCH_BUILD_TASK: "build-php-8.2"
+      PHP_VERSION: "8.2"
     depends_on:
       - variant: "build-debian11"
         name: "build-php-8.2"
@@ -24,6 +25,7 @@ buildvariants:
     expansions:
       FETCH_BUILD_VARIANT: "build-debian92"
       FETCH_BUILD_TASK: "build-php-8.2"
+      PHP_VERSION: "8.2"
     depends_on:
       - variant: "build-debian92"
         name: "build-php-8.2"
@@ -41,6 +43,7 @@ buildvariants:
     expansions:
       FETCH_BUILD_VARIANT: "build-debian11"
       FETCH_BUILD_TASK: "build-php-8.1"
+      PHP_VERSION: "8.1"
     depends_on:
       - variant: "build-debian11"
         name: "build-php-8.1"
@@ -53,6 +56,7 @@ buildvariants:
     expansions:
       FETCH_BUILD_VARIANT: "build-debian11"
       FETCH_BUILD_TASK: "build-php-8.0"
+      PHP_VERSION: "8.0"
     depends_on:
       - variant: "build-debian11"
         name: "build-php-8.0"
@@ -65,6 +69,7 @@ buildvariants:
     expansions:
       FETCH_BUILD_VARIANT: "build-debian11"
       FETCH_BUILD_TASK: "build-php-7.4"
+      PHP_VERSION: "7.4"
     depends_on:
       - variant: "build-debian11"
         name: "build-php-7.4"