generated tests are incomplete

[sakulstra]

in theory each feature can define generated tests, but most features only generate the default test yet
Probably makes sense to improve so reviews are easier/less repetitive.

### Features not yet covered with custom tests:
- [ ] borrowUpdates
- [ ] capsUpdates
- [ ] collateralsUpdates
- [ ] eModesUpdates
- [ ] eModesAssets
- [ ] priceFeedsUpdates
- [ ] rateUpdates