fix client config don't take effect

[yihuang]

Description

• Set keyring-backend in client.toml don't work, because keyring-dir is not set properly.
  Solution: set keyring-dir to home by default when reading client.toml.
• Some commands override what's set in client.toml even if not pass command line flag.
  Solution: keep client.toml value if flag not passed.

closes: #XXXX

---

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• Targeted PR against correct branch (see CONTRIBUTING.md)
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• Review Codecov Report in the comment section below once CI passes

[codecov]

Codecov Report

Merging #9211 (3a5a5f3) into master (9d05048) will decrease coverage by 0.65%.
The diff coverage is 72.72%.

❗ Current head 3a5a5f3 differs from pull request most recent head 9116210. Consider uploading reports for the commit 9116210 to get more accurate results

@@            Coverage Diff             @@
##           master    #9211      +/-   ##
==========================================
- Coverage   60.38%   59.72%   -0.66%     
==========================================
  Files         587      595       +8     
  Lines       36920    37348     +428     
==========================================
+ Hits        22294    22306      +12     
- Misses      12651    13060     +409     
- Partials     1975     1982       +7     

Impacted Files	Coverage Δ
client/keys/show.go	83.67% <33.33%> (-1.90%)	⬇️
client/keys/add.go	62.50% <83.33%> (ø)
client/config/config.go	54.83% <100.00%> (+1.50%)	⬆️
x/feegrant/keeper/grpc_query.go	0.00% <0.00%> (-81.40%)	⬇️
x/feegrant/keeper/msg_server.go	6.89% <0.00%> (-79.32%)	⬇️
x/bank/client/testutil/cli_helpers.go	8.10% <0.00%> (-41.90%)	⬇️
x/params/module.go	11.11% <0.00%> (-40.75%)	⬇️
types/codec.go	50.00% <0.00%> (-16.67%)	⬇️
store/internal/proofs/create.go	67.56% <0.00%> (-13.83%)	⬇️
x/authz/keeper/grpc_query.go	67.21% <0.00%> (-9.26%)	⬇️
... and 117 more

[cyberbono3]

@yihuang To scope the problem, can you provide some examples please for:

1. Set keyring-backend in client.toml don't work?
2. Some commands override what's set in client.toml even if not pass command line flag

You can use --home flag to set HomeDir. ReadHomeFlag checks if home flag is set. If this is a case, it updates HomeDir field of client. Context. Otherwise, it uses default HomeDir.

[amaury1093]

I reproduced the error, and this fix works. Approving.

Set keyring-backend in client.toml don't work?

Yeah, client.toml is correctly updated, but the CLI doesn't read from it.

[robert-zaremba]

utACK