fix: add iavl-cache-size config parsing to GetConfig (#10990)

## Description

Closes: #10982

Added missing iavl-cache-size config parsing to GetConfig.



---

### Author Checklist

*All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues.*

I have...

- [ ] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
- [ ] targeted the correct branch (see [PR Targeting](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#pr-targeting))
- [ ] provided a link to the relevant issue or specification
- [ ] followed the guidelines for [building modules](https://github.com/cosmos/cosmos-sdk/blob/master/docs/building-modules)
- [ ] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] included comments for [documenting Go code](https://blog.golang.org/godoc)
- [ ] updated the relevant documentation or specification
- [ ] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

*All items are required. Please add a note if the item is not applicable and please add
your handle next to the items reviewed if you only reviewed selected items.*

I have...

- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed 
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

CHANGELOG.md

@@ -177,6 +177,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * [\#10842](https://github.com/cosmos/cosmos-sdk/pull/10842) Fix error when `--generate-only`, `--max-msgs` fags set while executing `WithdrawAllRewards` command.
 * [\#10897](https://github.com/cosmos/cosmos-sdk/pull/10897) Fix: set a non-zero value on gas overflow.
 * [#9790](https://github.com/cosmos/cosmos-sdk/pull/10687) Fix behavior of `DecCoins.MulDecTruncate`.
+* [\#10990](https://github.com/cosmos/cosmos-sdk/pull/10990) Fixes missing `iavl-cache-size` config parsing in `GetConfig` method.
 * (crypto) [#11027] Remove dependency on Tendermint core for xsalsa20symmetric.
 
 ### State Machine Breaking

server/config/config.go

@@ -271,6 +271,7 @@ func GetConfig(v *viper.Viper) Config {
 			HaltTime:          v.GetUint64("halt-time"),
 			IndexEvents:       v.GetStringSlice("index-events"),
 			MinRetainBlocks:   v.GetUint64("min-retain-blocks"),
+			IAVLCacheSize:     v.GetUint64("iavl-cache-size"),
 		},
 		Telemetry: telemetry.Config{
 			ServiceName:             v.GetString("telemetry.service-name"),