fix glob version on lts tests

[mansona]

you can see in #621 that CI is currently failing because of a floating dependency on minimatch

this minimatch dependency floated because of the dependency chain ember-cli-babel@8 > babel-plugin-module-resolver@5 > glob@9 > minimatch@8

Edit: it turns out the original culprit is the fact that @embroider/util bumped the ember-cli-babel major version without doing a major themselves 😞 Looking at the full list of npm why minimatch@8 you can see why:

minimatch@8.0.4 dev
../../node_modules/@embroider/util/node_modules/minimatch
  minimatch@"^8.0.2" from glob@9.3.5
  ../../node_modules/@embroider/util/node_modules/glob
    glob@"^9.3.3" from babel-plugin-module-resolver@5.0.2
    ../../node_modules/@embroider/util/node_modules/babel-plugin-module-resolver
      babel-plugin-module-resolver@"^5.0.0" from ember-cli-babel@8.2.0
      ../../node_modules/@embroider/util/node_modules/ember-cli-babel
        ember-cli-babel@"^8.2.0" from @embroider/util@1.13.0
        ../../node_modules/@embroider/util
          @embroider/util@"^1.9.0" from @ember/test-helpers@2.9.4

Another edit: it turns out that there were other dependencies of glob@9 that needed a newer node version so instead of pinning minimatch I just pinned glob to the pre 9 version 👍