PHPLIB-565: Add MongoDB version axis to build matrix (#780)

* Allow overriding default cluster configurations

* Make phpunit output less verbose

* Use latest stable driver version

* Expand test matrix to test against all driver and server versions

* Add secondary servers to cluster replica set

* Make explain command check more forgiving

* Don't drop collections in admin database for spec tests

* Test against all topologies by default

* Use majority write concern when inserting external keyvault data

Author: alcaeus

.evergreen/config.yml

@@ -174,7 +174,7 @@ functions:
       params:
         script: |
           ${PREPARE_SHELL}
-          MONGODB_VERSION=${VERSION} TOPOLOGY=${TOPOLOGY} AUTH=${AUTH} SSL=${SSL} STORAGE_ENGINE=${STORAGE_ENGINE} sh ${DRIVERS_TOOLS}/.evergreen/run-orchestration.sh
+          MONGODB_VERSION=${VERSION} ORCHESTRATION_FILE=${ORCHESTRATION_FILE} TOPOLOGY=${TOPOLOGY} AUTH=${AUTH} SSL=${SSL} STORAGE_ENGINE=${STORAGE_ENGINE} sh ${PROJECT_DIRECTORY}/.evergreen/run-orchestration.sh
     # run-orchestration generates expansion file with the MONGODB_URI for the cluster
     - command: expansions.update
       params:
@@ -417,9 +417,7 @@ axes:
     display_name: Driver Version
     values:
       - id: "latest-stable"
-        display_name: "1.8.0beta2"
-        variables:
-          DRIVER_VERSION: "1.8.0beta2"
+        display_name: "1.8-stable"
       - id: "latest-minor-dev"
         display_name: "1.8-dev"
         variables:
@@ -507,10 +505,35 @@ axes:
 
 buildvariants:
 
-- matrix_name: "test-baseline"
-  matrix_spec: {"os-php7": ["debian92-test", "ubuntu1804-arm64-test", "rhel70-test"], "php-versions": "*", "versions": "4.4", "driver-versions": "latest-stable" }
+# Tests all PHP versions on all operating systems.
+# Only tests against latest MongoDB and ext-mongodb versions
+- matrix_name: "test-php-versions"
+  matrix_spec: {"os-php7": ["debian92-test", "ubuntu1804-arm64-test", "rhel70-test"], "php-versions": "*", "edge-versions": "latest-stable", "driver-versions": "latest-stable" }
   exclude_spec:
-    - { "os-php7": ["debian92-test", "rhel70-test"], "php-versions": "7.0", versions: "*", "driver-versions": "*" }
-  display_name: "${os-php7}, PHP ${php-versions}, MongoDB ${versions}, ext-mongodb ${driver-versions}"
+    - { "os-php7": ["debian92-test", "rhel70-test"], "php-versions": "7.0", edge-versions: "*", "driver-versions": "*" }
+  display_name: "PHP ${php-versions}, ${os-php7}, MongoDB ${edge-versions}, ext-mongodb ${driver-versions}"
   tasks:
     - name: "test-standalone"
+    - name: "test-replica_set"
+    - name: "test-sharded_cluster"
+
+# Tests all driver versions on all PHP versions
+# Only tests on Ubuntu 18.04 and latest MongoDB
+- matrix_name: "test-driver-versions"
+  matrix_spec: {"os-php7": "ubuntu1804-arm64-test", "php-versions": "*", "edge-versions": "latest-stable", "driver-versions": "*" }
+  display_name: "ext-mongodb ${driver-versions}, PHP ${php-versions}, ${os-php7}, MongoDB ${edge-versions}"
+  tasks:
+    - name: "test-standalone"
+    - name: "test-replica_set"
+    - name: "test-sharded_cluster"
+
+# Tests all MongoDB versions
+# Only tests on Ubuntu 18.04, with latest stable PHP and driver versions
+# Tests against various topologies
+- matrix_name: "test-mongodb-versions"
+  matrix_spec: {"os-php7": "rhel70-test", "php-edge-versions": "latest-stable", "versions": "*", "driver-versions": "latest-stable" }
+  display_name: "MongoDB ${versions}, PHP ${php-edge-versions}, ${os-php7}, ext-mongodb ${driver-versions}"
+  tasks:
+    - name: "test-standalone"
+    - name: "test-replica_set"
+    - name: "test-sharded_cluster"