Deprecate SetFullFundraiserPath in favor of SetPurpose and SetCoinType

[RiccardoM]

Description

This PR removes the SetFullFundraiserPath method in favor of distinct SetPurpose and SetCoinType methods. It also renames the GetFullFundraiserPath method to GetFullBip44Path.

This is done in order to simplify the code that chains should write when using a custom coin type. Right now, they must call two distinct methods:

cfg.SetCoinType(customCoinType)
cfg.SetFullFundraiserPath(customPath)

With this PR, it would be simplified to

cfg.SetCoinType(customCoinType)

This because the BIP-44 path is now generated considering the data put inside the sdk.Config object instead of taking the full path from outside.

---

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write a little note why.

• Targeted PR against correct branch (see CONTRIBUTING.md)
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
• Code follows the module structure standards.
• Wrote unit and integration tests
• Updated relevant documentation (docs/) or specification (x/<module>/spec/)
• Added relevant godoc comments.
• Added a relevant changelog entry to the Unreleased section in CHANGELOG.md
• Re-reviewed Files changed in the Github PR explorer
• Review Codecov Report in the comment section below once CI passes

[codecov]

Codecov Report

Merging #8629 (c25205e) into master (0b3af0e) will increase coverage by 0.00%.
The diff coverage is 88.88%.

@@           Coverage Diff           @@
##           master    #8629   +/-   ##
=======================================
  Coverage   61.47%   61.47%           
=======================================
  Files         659      659           
  Lines       37876    37881    +5     
=======================================
+ Hits        23283    23287    +4     
- Misses      12159    12160    +1     
  Partials     2434     2434           

Impacted Files	Coverage Δ
types/address.go	65.99% <ø> (ø)
x/authz/types/authorization_grant.go	0.00% <ø> (ø)
x/staking/types/authz.go	87.87% <ø> (ø)
types/config.go	84.28% <88.88%> (-0.33%)	⬇️

[fedekunze]

ACK. Please add an API breaking change Changelog entry

[RiccardoM]

ACK. Please add an API breaking change Changelog entry

Added

[alessio]

Instead of removing SetFullFundraiserPath() and GetFullFundraiserPath(), I'd like to see both functions being marked as deprecated. We'll remove them in a future release. An example of a deprecation comment follows:

// ModTime returns the modification time in UTC using the legacy
// ModifiedDate and ModifiedTime fields.
//
// Deprecated: Use Modified instead.
func (h *FileHeader) ModTime() time.Time {
	return msDosTimeToTime(h.ModifiedDate, h.ModifiedTime)
}

[RiccardoM]

Instead of removing SetFullFundraiserPath() and GetFullFundraiserPath(), I'd like to see both functions being marked as deprecated.

Done 👍