[Feat]: added download tarball button at list

[anikethsaha]

Type:
Feature

The following has been addressed in the PR:

• There is a related issue? https://github.com/verdaccio/ui/issues/217
• Unit or Functional tests are included in the PR ! Yes (updated the snapshots)

Description:
Added the download package button in the package list from the main page

[codecov]

Codecov Report

Merging #237 into master will decrease coverage by 0.07%.
The diff coverage is 66.66%.

@@            Coverage Diff             @@
##           master     #237      +/-   ##
==========================================
- Coverage   90.31%   90.23%   -0.08%     
==========================================
  Files         139      139              
  Lines         919      922       +3     
  Branches      142      161      +19     
==========================================
+ Hits          830      832       +2     
+ Misses         77       75       -2     
- Partials       12       15       +3

Impacted Files	Coverage Δ
src/components/Package/Package.tsx	96.42% <66.66%> (-3.58%)	⬇️
src/utils/styles/media.ts	81.81% <0%> (ø)	⬆️
src/components/DetailSidebar/DetailSidebar.tsx	85% <0%> (ø)	⬆️

[juanpicado]

🚀 super nice !