Evaluate nested floor/ceiling.

[sbt4104]

References to other Issues or PRs

Fixes #18689

Brief description of what is fixed or changed

evaluate nested floor and ceiling.
example-

floor(floor(floor(x)) + 3) == floor(x) + 3
ceiling(ceiling(ceiling(x)) + 3) == ceiling(x) + 3
ceiling(ceiling(floor(x)) + 3) == floor(x) + 3

Release Notes

• functions
  • Evaluate nested floor/ceiling.

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• functions
  • Evaluate nested floor/ceiling. (#18903 by @sbt4104)

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#### References to other Issues or PRs
Fixes #18689 

#### Brief description of what is fixed or changed
evaluate nested floor and ceiling.
example-
```python
floor(floor(floor(x)) + 3) == floor(x) + 3
ceiling(ceiling(ceiling(x)) + 3) == ceiling(x) + 3
ceiling(ceiling(floor(x)) + 3) == floor(x) + 3
```
### Release Notes
<!-- BEGIN RELEASE NOTES -->
* functions
    - Evaluate nested floor/ceiling.
<!-- END RELEASE NOTES -->

Update

The release notes on the wiki have been updated.

[Smit-create]

Please add test cases for the change you have made

[codecov]

Codecov Report

Merging #18903 into master will increase coverage by 0.012%.
The diff coverage is 100%.

@@              Coverage Diff              @@
##            master    #18903       +/-   ##
=============================================
+ Coverage   75.649%   75.662%   +0.012%     
=============================================
  Files          647       647               
  Lines       168517    168520        +3     
  Branches     39707     39710        +3     
=============================================
+ Hits        127483    127507       +24     
+ Misses       35474     35456       -18     
+ Partials      5560      5557        -3

[smichr]

Looks good.