tests: tweak Jasmine usage (#32046)

* jasmine/expect-matcher
* jasmine/prefer-jasmine-matcher

Found with `eslint-plugin-jasmine`

js/tests/unit/modal.spec.js

@@ -637,7 +637,7 @@ describe('Modal', () => {
       modalEl.addEventListener('shown.bs.modal', () => {
         modalEl.click()
         setTimeout(() => {
-          expect(modalEl.clientHeight === modalEl.scrollHeight).toEqual(true)
+          expect(modalEl.clientHeight).toEqual(modalEl.scrollHeight)
           done()
         }, 20)
       })