Aggregate queries follow up (#9581)

In this PR

- fixing Collapse on view groups views: aggregate bar should be included
in the collapse (@magrinj )
- respect the html table pattern: the aggregate bar is now a <tr>
element included in a <table> (before that, it was a <tr> not included
in anything)
- add a top-border on the aggregate bar
- introduce short labels for the on-cell value display (display "Empty"
instead of "Count empty" to lighten the interface)
- remove the feature flag !

packages/twenty-front/src/generated-metadata/graphql.ts

@@ -389,7 +389,6 @@ export type FeatureFlagFilter = {
 
 export enum FeatureFlagKey {
   IsAdvancedFiltersEnabled = 'IsAdvancedFiltersEnabled',
-  IsAggregateQueryEnabled = 'IsAggregateQueryEnabled',
   IsAirtableIntegrationEnabled = 'IsAirtableIntegrationEnabled',
   IsAnalyticsV2Enabled = 'IsAnalyticsV2Enabled',
   IsCommandMenuV2Enabled = 'IsCommandMenuV2Enabled',