fix: support output flag on tx commands (backport cosmos#9717) (cosmo…

…s#9771)

* fix: support output flag on tx commands (cosmos#9717)

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## Description

Closes: cosmos#9684

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---

### Author Checklist

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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

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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)

(cherry picked from commit 9253503)

* Fix changelog

Co-authored-by: Sai Kumar <17549398+gsk967@users.noreply.github.com>
Co-authored-by: Amaury M <1293565+amaurym@users.noreply.github.com>

CHANGELOG.md

@@ -35,6 +35,12 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 # Changelog
 
+## [Unreleased]
+
+### Improvements
+
+* (cli) [\#9717](https://github.com/cosmos/cosmos-sdk/pull/9717) Added CLI flag `--output json/text` to `tx` cli commands.
+
 ## [v0.43.0-rc2](https://github.com/cosmos/cosmos-sdk/releases/tag/v0.43.0-rc2) - 2021-07-19
 
 ### Bug Fixes