add pushed charts to cached index

[alice-sawatzky]

when pushing a chart, it would be nice if the chart was added to the local repo index cache immediately, instead of requiring a slow helm repo update. My current CI workflow would speed up quite a bit if it didn't need to re-fetch the chart index it just pushed to to be able to pull the chart.

[sagikazarmark]

I wonder: what makes the repo update so slow, that this change would cause a considerable performance gain? I mean, it's only one file you have to download.

[alice-sawatzky]

i'm not sure, but it takes several hundred ms, and with a lot of repos that adds up