CompatHelper: bump compat for Turing to 0.28 for package turing, (keep existing compat) (#509)

Co-authored-by: CompatHelper Julia <[email protected]>

Author: github-actions[bot]

test/turing/Project.toml

@@ -7,5 +7,5 @@ Turing = "fce5fe82-541a-59a6-adf8-730c64b5f9a0"
 
 [compat]
 DynamicPPL = "0.20, 0.21, 0.22, 0.23"
-Turing = "0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27"
+Turing = "0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28"
 julia = "1.6"