test(eslint-plugin): adjust tests to verify `no-unnecessary-type-assertion` doesn't report template literals with expressions#10671

JoshuaKGoldberg merged 2 commits intotypescript-eslint:maintypescript-eslint/typescript-eslint:mainfrom

ronami:fix-no-unnecessary-type-assertion-template-literal-testsronami/typescript-eslint:fix-no-unnecessary-type-assertion-template-literal-testsCopy head branch name to clipboard