Upgrade Go SQL driver for MySQL

[elikatsis]

We (Arrikto) have been deploying multi-user KFP as part of KF with Istio sidecars. We have noticed that some Istio connection resets made the KFP API server <-> MySQL db communication break. And this was happening a lot.
We were essentially bumping into this issue: go-sql-driver/mysql#674

So after some research, we found out that we are currently using an old version of the Go SQL driver for MySQL.

We have lots of reasons to upgrade it, see here for a great article on this. It contains a summary of important bugs which got fixed in v1.5.0.

After upgrading it for our deployments, this issue was greatly eliminated to the point that it almost never happens [or on the very rare occasion that it may occur, it is totally unnoticeable].