Add example to AngleEmbedding

[ankit27kh]

Add example in documentation

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Context:
Some templates do not have examples.
Description of the Change:
Add example to AngleEmbedding documentation
Benefits:
Better documentation
Possible Drawbacks:
N/A
Related GitHub Issues:
#1727 #1735

[ankit27kh]

Hi @antalszava! Is this example acceptable? If yes, similar examples can be made in all templates with further details where necessary.

[codecov]

Codecov Report

Merging #1908 (5ff9140) into master (80a169d) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1908   +/-   ##
=======================================
  Coverage   98.85%   98.85%           
=======================================
  Files         220      220           
  Lines       16972    16972           
=======================================
  Hits        16778    16778           
  Misses        194      194           

Impacted Files	Coverage Δ
pennylane/templates/embeddings/angle.py	100.00% <ø> (ø)

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[antalszava]

Hi @ankit27kh, thank you for the addition! 😊

Hi @antalszava! Is this example acceptable? If yes, similar examples can be made in all templates with further details where necessary.

Yep, this looks awesome! Left some minor comments, but such examples look great. Let me know if you'd like us to leave a review. Don't forget to update the changelog file! 🙂

[ankit27kh]

@antalszava this seems ready then. I'll probably add examples to other templates one at a time. As there are a lot of templates, I will be making separate PRs. Small chunks are easy to manage. 😄

[antalszava]

Looks good! Thank you 🙂 Other PRs adding new template examples could also just extend the item added in the changelog by another line with the PR number. 👍