Convert primaryKey value to int if it is numeric

Merge branch 'master' of https://github.com/contributte/datagrid

phpstan.neon made more readable

package.json fix

Readme: fix badges (vol2)

Fix ExportCsv blank output

Regression from a56c9d3, which results in rows with no columns (since `getColumns` never returns `null`).

Std [004]: kodiak

docs

composer: allows PHP 8.0

package.json