SQL: consider adding the IN operator support

[astefan]

At the moment the workaround for the missing IN support is to provide a long list of OR statements. It would be easier/more comfortable to use IN instead.
Related to #32942

[elasticmachine]

Pinging @elastic/es-search-aggs

[lanerjo]

+1
WHERE visit.app.appName IN ('appA', 'appB') <- does not work
terms: {visit.app.appName: [appA, appB]} <- expected translation of above

WHERE visit.app.appName = appA OR visit.app.appName = appB <- very very very inconvenient workaround