fix(CDN#icon): remove guild prefixes

[vaporoxx]

Please describe the changes this PR makes and why it should be merged:

Cleans up some rebase oopsies from #53

Status and versioning classification:

• I know how to update typings and have done so

[codecov]

Codecov Report

Merging #67 (7221121) into main (65cb8e2) will not change coverage.
The diff coverage is 50.00%.

@@           Coverage Diff           @@
##             main      #67   +/-   ##
=======================================
  Coverage   85.84%   85.84%           
=======================================
  Files           8        8           
  Lines        1010     1010           
  Branches      101      101           
=======================================
  Hits          867      867           
  Misses         42       42           
  Partials      101      101           

Impacted Files	Coverage Δ
packages/rest/src/lib/CDN.ts	86.74% <50.00%> (ø)

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[kyranet]

I don't know why Coverage dropped without changes but... LGTM!