Updates opam file and the reference configuration for yojson 2.0.

opam

@@ -121,7 +121,7 @@ depends: [
   "ocamlfind" # needed beyond build stage, used by -load-module
   "ocamlgraph" { >= "1.8.8" }
   "why3" { >= "1.5.1" }
-  "yojson" {>= "1.6.0" & (< "2.0.0" | !with-test)}
+  "yojson" {>= "1.6.0" & (>= "2.0.1" | !with-test)}
   "zarith" { >= "1.5" }
 
   # PPXs

reference-configuration.md

@@ -14,5 +14,5 @@ compiling Frama-C+dev.
 - ppx_deriving_yojson.3.7.0
 - ppx_import.1.10.0
 - why3.1.5.1
-- yojson.1.7.0
+- yojson.2.0.2
 - zarith.1.12