CompatHelper: bump compat for "Zygote" to "0.5"

[github-actions[bot]]

This pull request changes the compat entry for the Zygote package from 0.3, 0.4 to 0.3, 0.4, 0.5.

This keeps the compat entries for earlier versions.

Note: I have not tested your package with this new compat entry. It is your responsibility to make sure that your package tests pass before you merge this pull request.

[coveralls]

Pull Request Test Coverage Report for Build 451

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 2 unchanged lines in 1 file lost coverage.
• Overall coverage increased (+0.05%) to 74.924%

---

Files with Coverage Reduction	New Missed Lines	%
src/kernels/mat.jl	2	83.87%
<!--	Total:	2		-->

Totals
Change from base Build 445:	0.05%
Covered Lines:	1482
Relevant Lines:	1978

---

💛 - Coveralls