chore: allow ht link to support null from async pipe

[aaron-steinfeld]

Description

When used with async pipe, link would error on initial null state.

[codecov]

Codecov Report

Merging #893 (535c9c2) into main (5143237) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main     #893   +/-   ##
=======================================
  Coverage   85.36%   85.37%           
=======================================
  Files         801      801           
  Lines       16472    16475    +3     
  Branches     2067     2067           
=======================================
+ Hits        14062    14065    +3     
  Misses       2378     2378           
  Partials       32       32           

Impacted Files	Coverage Δ
projects/components/src/link/link.component.ts	100.00% <100.00%> (ø)

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[github-actions]

Unit Test Results

    4 files  256 suites   14m 34s ⏱️
923 tests 923 ✔️ 0 💤 0 ❌
929 runs  929 ✔️ 0 💤 0 ❌

Results for commit 47f4f31.