Move Gateway compatibility tests to smoke-test (#7085)

Previously, we installed six versions of `@apollo/gateway` via the
monorepo package.json, which we used as part of the test suite to check
to see if `new ApolloServer({gateway: new ApolloGateway()})` compiled
(and ran, but not actually started/served).

Some of these versions are quite old and require `--no-engine-strict` to
install under Node v18 (because our `.npmrc` sets `engine-strict` to
true for some reason). Now that Node v18 is LTS, Renovate wants to start
using v18 itself and upgrade us to v18, but it's running into trouble
due to these failures.

We take the easy way out and move this test to the `smoke-test`
directory. Now we don't install these `@apollo/gateway` versions unless
we're actively running the smoke test. (This also means we no longer
have AS3 in our package-lock.json!)

Fixes #7078.

Author: glasser

.changeset/hip-years-repair.md

@@ -0,0 +1,2 @@
+---
+---

.circleci/config.yml

@@ -28,23 +28,7 @@ commands:
           - run: volta pin node@<< parameters.node-version >>
       - run: node --version
       - run: npm --version
-      # For now, we ignore `engine` constraints in package.json when running on
-      # Node 18. That's because we install a bunch of versions of
-      # @apollo/gateway for compatibility testing, including some from the era
-      # where we liked putting `<` engine constraints on all our packages. If
-      # this gets awkward, we can stop testing those old versions, or test them
-      # somewhere more self-contained like the smoke-test.
-      - when:
-          condition:
-            equal: [ '18', << parameters.node-version >> ]
-          steps:
-            - node/install-packages:
-                override-ci-command: npm ci --no-engine-strict
-      - unless:
-          condition:
-            equal: [ '18', << parameters.node-version >> ]
-          steps:
-            - node/install-packages
+      - node/install-packages
 
 
 jobs:
@@ -79,9 +63,7 @@ jobs:
           node-version: "18"
       # Install a prerelease of graphql-js 17 with incremental delivery support.
       # --legacy-peer-deps because nothing expects v17 yet.
-      # --no-engine-strict because Node v18 doesn't match the engines fields
-      # on some old stuff.
-      - run: npm i --legacy-peer-deps --no-engine-strict graphql@17.0.0-alpha.1.canary.pr.3361.04ab27334641e170ce0e05bc927b972991953882
+      - run: npm i --legacy-peer-deps graphql@17.0.0-alpha.1.canary.pr.3361.04ab27334641e170ce0e05bc927b972991953882
       - run: npm run test:ci
       - run: npm run test:smoke