Add typed events and metrics to the Attribute module

[channa-figure]

Description

Implementation of typed events and metrics for the attribute module.
closes: #86

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Before we can merge this PR, please make sure that all the following items have been
checked off. If any of the checklist items are not applicable, please leave them but
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.
• 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 #279 (cf0782b) into main (eede82d) will decrease coverage by 0.12%.
The diff coverage is 12.76%.

@@            Coverage Diff             @@
##             main     #279      +/-   ##
==========================================
- Coverage   50.24%   50.12%   -0.13%     
==========================================
  Files         119      122       +3     
  Lines       11025    11115      +90     
==========================================
+ Hits         5540     5571      +31     
- Misses       4938     4995      +57     
- Partials      547      549       +2     

Impacted Files	Coverage Δ
x/attribute/keeper/msg_server.go	1.44% <0.00%> (-0.83%)	⬇️
x/attribute/types/events.go	0.00% <0.00%> (ø)
x/attribute/keeper/keeper.go	70.19% <60.00%> (-1.09%)	⬇️
x/attribute/handler.go	81.81% <0.00%> (ø)
x/attribute/module.go	47.05% <0.00%> (ø)

[dwedul-figure]

LGTM