docs: replace links in apps with correct ones (cosmos#1255)

## Description

I noticed that 2 links at the bottom of the applications docs page were not correct.

closes: #XXXX

---

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- [ ] Code follows the [module structure standards](https://github.com/cosmos/cosmos-sdk/blob/master/docs/building-modules/structure.md).
- [ ] Wrote unit and integration [tests](https://github.com/cosmos/ibc-go/blob/master/CONTRIBUTING.md#testing)
- [ ] Updated relevant documentation (`docs/`) or specification (`x/<module>/spec/`)
- [ ] Added relevant `godoc` [comments](https://blog.golang.org/godoc-documenting-go-code).
- [ ] Added a relevant changelog entry to the `Unreleased` section in `CHANGELOG.md`
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Author: crodriguezvega

docs/ibc/apps.md

@@ -464,13 +464,13 @@ which implements everything discussed above.
 Here are the useful parts of the module to look at:
 
 [Binding to transfer
-port](https://github.com/cosmos/ibc-go/blob/main/modules/apps/transfer/types/genesis.go)
+port](https://github.com/cosmos/ibc-go/blob/main/modules/apps/transfer/keeper/genesis.go)
 
 [Sending transfer
 packets](https://github.com/cosmos/ibc-go/blob/main/modules/apps/transfer/keeper/relay.go)
 
 [Implementing IBC
-callbacks](https://github.com/cosmos/ibc-go/blob/main/modules/apps/transfer/module.go)
+callbacks](https://github.com/cosmos/ibc-go/blob/main/modules/apps/transfer/ibc_module.go)
 
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