there is currently no way to hide or suppress shard errors in Kibana. I also don't think that we ever want that, since shard failures could basically lead to completely wrong data from what you're expecting, so it's important that the user is aware of that.
Since 7.4.0, the error message also got a bit more details and stating that this error means you could have incomplete data shown (you can see screenshots in https://github.com/elastic/kibana/pull/41649)
In general having shard errors is not a "okay I can ignore that" error, that should appear during normal usage. So if you're seeing shard errors, I would highly recommend digging into how those can happen. It could either be (as Rashmi pointed out), that your shards are unstable, and thus your Elasticsearch is not in a stable state, or you potentially have Scripted fields, that are broken and cause exceptions in some shards.
If you give more details about the shards that failed, we could help you with that. If you're running 7.4 or newer, you just need to check the "More details" button in that error and can copy the whole error here, before that, you need to open your browser console and look into the request that actually failed for the error.