test(NODE-4669): use node 18 in container (#150)

Author: durran

.evergreen/config.yml

@@ -177,5 +177,6 @@ buildvariants:
       packager_distro: ubuntu2004
       packager_arch: arm64
     tasks:
+      - run-tests-ubuntu
       - run-prebuild
       - run-prebuild-force-publish

.evergreen/run-tests-ubuntu.sh

@@ -126,10 +126,10 @@ fi
 source "${PROJECT_DIRECTORY}/.evergreen/install-dependencies.sh"
 
 set -o xtrace
-echo "Run: nvm install 14"
-nvm install 14
-echo "Run: nvm use 14"
-nvm use 14
+echo "Run: nvm install 18"
+nvm install 18
+echo "Run: nvm use 18"
+nvm use 18
 set +o xtrace