Fix failing md2d scripting api tests

[#60338690]

Call scriptingAPI.exposeScriptingAPI() after binding a new model...

This doesn't seem like a necessary step. However, without it md2d-scripting-api
tests fail, but only when all tests are run (e.g. make test-src)! When you run just this
single test everything works (e.g. mocha test/md2d/md2d-scripting-api). It looks like
window.script variable references some old API instance and seems to be related to the
test environment setup. Temporarily put this call here for safety.