Inconsistent ETag handling in `postBundleContents` and `deleteContentItem`

[zerolab]

Adding a dataset to a bundle updates the bundle ETag and that is returned in the response

dis-bundle-api/api/contents.go

Line 192 in bd5e752

bundleUpdate, err := api.stateMachineBundleAPI.UpdateBundleETag(ctx, bundleID, authEntityData.GetUserEmail())

dis-bundle-api/api/contents.go

Line 216 in bd5e752

dpresponse.SetETag(w, bundleUpdate.ETag)

Deleting a content item (i.e. dataset) from a bundle does't seem to update its ETag at all

dis-bundle-api/api/contents.go

Line 327 in bd5e752

w.WriteHeader(http.StatusNoContent)