Add linter to catch use of %v and %+v

[theunrepentantgeek]

Describe the improvement

Those format specifiers can cause leakage of PII in logs, which is a Bad Thing(tm).

We've eliminated all the uses of %v and %+v but should now turn on the linter to make sure we stay clean.

[theunrepentantgeek]

I asked around:

Anyone know the name of the linter that catches %v and %+v format specifiers in code?
We want to turn this on in the azure-service-operator repo but my Google abilities are failing me and I haven't been able to work out which linter to use. #thanksinadvance

and got this response:

IIRC, we wrote a special script to detect the %v / %+v usage instead of using a linter ...

So I'll write a check for the build script.