perf(store): postgres transactions

[jakubdyszkiewicz]

Checklist prior to review

Introducing postgres transactions.
This PR does NOT introduce need for transactions in Kuma, this is just a perf optimization for stores that support transactions.

Enrich ResourceStore vs new interface

I introduced a new interface called Transactions, so the transaction can be used by either ResourceStore and ResourceManager. If I would add a new method in ResourceStore we would also add this to ResourceManager.

Transaction in Context vs store opts

I decided to propagate transaction implicitly in context instead of explicitly in store opts like CreateInTx(tx). This is more flexible with less changes to the code. We could also for example open a transaction when we create new Mesh without adding CreateInTx to every call.

• Link to relevant issue as well as docs and UI issues --
• This will not break child repos: it doesn't hardcode values (.e.g "kumahq" as a image registry) and it will work on Windows, system specific functions like syscall.Mkfifo have equivalent implementation on the other OS --
• Tests (Unit test, E2E tests, manual test on universal and k8s) --
• Do you need to update UPGRADE.md? --
• Does it need to be backported according to the backporting policy? (this GH action will add "backport" label based on these file globs, if you want to prevent it from adding the "backport" label use no-backport-autolabel label) --
• Do you need to explicitly set a > Changelog: entry here or add a ci/ label to run fewer/more tests?