CompatHelper: bump compat for DocumenterMermaid to 0.2 for package docs, (keep existing compat)

Author: CompatHelper Julia

docs/Project.toml

@@ -16,7 +16,7 @@ Accessors = "0.1"
 DataStructures = "0.18"
 Distributions = "0.25"
 Documenter = "1"
-DocumenterMermaid = "0.1"
+DocumenterMermaid = "0.1, 0.2"
 FillArrays = "0.13, 1"
 ForwardDiff = "0.10"
 JET = "0.9"