Invalidate for async setting of icache

[agubler]

Type: feature

The following has been addressed in the PR:

• There is a related issue
• All code has been formatted with prettier as per the readme code style guidelines
• Unit or Functional tests are included in the PR

Description:

In order to be able to react to a "pending" state of an icache value we need to call invalidate at the start of calling the async setter and then also on the resolution.

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[codecov]

Codecov Report

Merging #865 (9b1012b) into master (86011f5) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #865   +/-   ##
=======================================
  Coverage   94.72%   94.73%           
=======================================
  Files         127      127           
  Lines        8095     8103    +8     
  Branches     1889     1891    +2     
=======================================
+ Hits         7668     7676    +8     
  Misses        427      427           

Impacted Files	Coverage Δ
src/core/middleware/icache.ts	100.00% <100.00%> (ø)

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