Handle async functions in depends with watch=True

[philippjfr]

Required for holoviz/panel#3262 to work

[codecov-commenter]

Codecov Report

Merging #611 (70b7d4c) into master (fb6f4d9) will decrease coverage by 0.15%.
The diff coverage is 41.66%.

@@            Coverage Diff             @@
##           master     #611      +/-   ##
==========================================
- Coverage   81.95%   81.79%   -0.16%     
==========================================
  Files           4        4              
  Lines        3020     3027       +7     
==========================================
+ Hits         2475     2476       +1     
- Misses        545      551       +6     

Impacted Files	Coverage Δ
param/parameterized.py	81.89% <41.66%> (-0.30%)	⬇️

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