ci(workflows): Update inputs on dry run workflows

For MATS and XTS dry runs we need to remove the secondary branch input:

| MATS | XTS |
| :-----: | :---: |
| [MATS-Dry-Run](https://github.com/hiero-ledger/hiero-consensus-node/blob/main/.github/workflows/flow-dry-run-mats-suite.yaml) | [XTS-Dry-Run](https://github.com/hiero-ledger/hiero-consensus-node/blob/main/.github/workflows/flow-dry-run-extended-test-suite.yaml) |
| | |

This ensures that the user is running the dry-run from the github branch/tag selector.

Documentation will need to be updated as well at [.github/workflows/docs](https://github.com/hiero-ledger/hiero-consensus-node/tree/main/.github/workflows/docs)