test: add HTTP tests that cover actual behaviours

[faustbrian]

The previous HttpClient tests mocked everything which meant nothing was actually tested. The tests now use fake response with nock which makes sure that requests are sent to the correct URLs and return an actual response body.

Replaced axios with node-fetch because it was causing problems with nock but both of them anyways are just temporary solutions because something else will have to be used to support proxies.

[codecov]

Codecov Report

Merging #2174 into 3.0-react will not change coverage.
The diff coverage is 100.00%.

@@             Coverage Diff              @@
##           3.0-react     #2174    +/-   ##
============================================
  Coverage     100.00%   100.00%            
============================================
  Files             24       112    +88     
  Lines            142       882   +740     
  Branches          18       136   +118     
============================================
+ Hits             142       882   +740     

Flag	Coverage Δ
#unit	100.00% <100.00%> (?)

Impacted Files	Coverage Δ
src/app/components/Button/Button.tsx	100.00% <ø> (ø)
src/app/components/Card/Card.tsx	100.00% <ø> (ø)
src/app/components/Card/CardControl.tsx	100.00% <ø> (ø)
src/app/components/StepIndicator/StepIndicator.tsx	100.00% <ø> (ø)
src/app/components/Address/Address.tsx	100.00% <100.00%> (ø)
src/app/components/Address/utils.ts	100.00% <100.00%> (ø)
src/app/components/Alert/Alert.tsx	100.00% <100.00%> (ø)
src/app/components/Badge/Badge.styles.ts	100.00% <100.00%> (ø)
src/app/components/Badge/Badge.tsx	100.00% <100.00%> (ø)
src/app/components/Button/Button.styles.ts	100.00% <100.00%> (ø)
... and 142 more

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