Use S.Zero for refine.

[sylee957]

References to other Issues or PRs

Brief description of what is fixed or changed

I had found some other mistakes for refining re and im because of the type issues, while reviewing #17696
refine does not sanitizes the output types, so it can be a gotcha that some authors can make.

Other comments

Release Notes

• assumptions
  • Fixed refine(re(x), Q.imaginary(x)) giving python zero instead of sympy zero.
  • Fixed refine(im(x), Q.real(x)) giving python zero instead of sympy zero.

[sympy-bot]

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• assumptions

  • Fixed refine(re(x), Q.imaginary(x)) giving python zero instead of sympy zero. (#17700 by @sylee957)

  • Fixed refine(im(x), Q.real(x)) giving python zero instead of sympy zero. (#17700 by @sylee957)

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#### References to other Issues or PRs
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#### Brief description of what is fixed or changed

I had found some other mistakes for refining `re` and `im` because of the type issues, while reviewing #17696 
`refine` does not sanitizes the output types, so it can be a gotcha that some authors can make.

#### Other comments


#### Release Notes

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<!-- BEGIN RELEASE NOTES -->
- assumptions
  - Fixed `refine(re(x), Q.imaginary(x))` giving python zero instead of sympy zero.
  - Fixed `refine(im(x), Q.real(x))` giving python zero instead of sympy zero.
<!-- END RELEASE NOTES -->

Update

The release notes on the wiki have been updated.

[codecov]

Codecov Report

Merging #17700 into master will increase coverage by 0.024%.
The diff coverage is 100%.

@@              Coverage Diff              @@
##            master    #17700       +/-   ##
=============================================
+ Coverage   74.679%   74.703%   +0.024%     
=============================================
  Files          634       634               
  Lines       165737    165737               
  Branches     38979     38979               
=============================================
+ Hits        123771    123811       +40     
+ Misses       36484     36437       -47     
- Partials      5482      5489        +7

[oscarbenjamin]

Looks good