feat: allow model selection in client

[ZiniuYu]

This pr allows the user to select the model in the client when multiple models are running.

Sample usage:

from clip_client import Client

c = Client(xxx)
c.encode(xxx, parameters={'model': 'RN50'})
c.rank(xxx, parameters={'model': 'RN50'})

[codecov]

Codecov Report

Merging #775 (af6c80f) into main (bc6b72e) will increase coverage by 0.05%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #775      +/-   ##
==========================================
+ Coverage   81.85%   81.91%   +0.05%     
==========================================
  Files          17       17              
  Lines        1251     1255       +4     
==========================================
+ Hits         1024     1028       +4     
  Misses        227      227              

Flag	Coverage Δ
cas	81.91% <100.00%> (+0.05%)	⬆️

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Impacted Files	Coverage Δ
client/clip_client/client.py	86.66% <100.00%> (+0.27%)	⬆️

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[numb3r3]

Suggested change

	on=endpoint,
	on=f'/encode/{model_name}',

[ZiniuYu]

are we introducing extra '/'?

[github-actions]

📝 Docs are deployed on https://ft-client_model_select--jina-docs.netlify.app 🎉