chore: val instead of unneeded var in classes.md (#2546)
chore: val instead of unneeded var in classes.md (#2546)

Mutation to MutableLists should be done not by reassigning the property, but by modifying the list.  Otherwise, you can get nasty ambiguity errors with e.g. +=.
hltj/kotlin-web-site-cn,JetBrains/kotlin-web-site,JetBrains/kotlin-web-site,JetBrains/kotlin-web-site,JetBrains/kotlin-web-site,hltj/kotlin-web-site-cn,JetBrains/kotlin-web-site,hltj/kotlin-web-site-cn,JetBrains/kotlin-web-site,hltj/kotlin-web-site-cn,hltj/kotlin-web-site-cn,hltj/kotlin-web-site-cn