Added function zeros to DomainMatrix class

[ks147]

Brief description of what is fixed or changed

zeros function returning DomainMatrix of zeros in polys.matrices

Release Notes

• polys
  • Add zeros method to DomainMatrix

[sympy-bot]

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• polys
  • Add zeros method to DomainMatrix (#21015 by @ks147)

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#### Brief description of what is fixed or changed
zeros function returning DomainMatrix of zeros in polys.matrices 

#### Release Notes

<!-- BEGIN RELEASE NOTES -->
* polys
  * Add zeros method to DomainMatrix
<!-- END RELEASE NOTES -->

Update

The release notes on the wiki have been updated.

[ks147]

@oscarbenjamin please review

[oscarbenjamin]

Looks good. Thanks!