feat: add assets to eventstore and event (#1674)

* fix: add assets to eventstore and event

* fix: project member, grant member, app changed tests

* fix: asset migrations

* feat: add asset tests

* feat: add asset tests

* Update internal/eventstore/repository/repository.go

Co-authored-by: Livio Amstutz <livio.a@gmail.com>

* feat: add asset tests

Co-authored-by: Livio Amstutz <livio.a@gmail.com>

internal/eventstore/repository/asset.go

@@ -0,0 +1,24 @@
+package repository
+
+//Asset represents all information about a asset (img)
+type Asset struct {
+	// ID is to refer to the asset
+	ID string
+	//Asset is the actual image
+	Asset []byte
+	//Action defines if asset should be added or removed
+	Action AssetAction
+}
+
+type AssetAction int32
+
+const (
+	AssetAdded AssetAction = iota
+	AssetRemoved
+
+	assetCount
+)
+
+func (f AssetAction) Valid() bool {
+	return f >= 0 && f < assetCount
+}