Update Cobalt to 0.7.2

 - Support printing and parsing hex float literals
 - Fix string.format "%q"'s handling of nan and inf (Kan18)
 - Fix string is-letter/is-digit patterns treating characters as
   unicode.
 - tostring(...) now uses __name.

gradle/libs.versions.toml

@@ -19,8 +19,8 @@ parchmentMc = "1.19.4"
 asm = "9.3"
 autoService = "1.0.1"
 checkerFramework = "3.32.0"
-cobalt = "0.7.1"
-cobalt-next = "0.7.2" # Not a real version, used to constrain the version we accept.
+cobalt = "0.7.2"
+cobalt-next = "0.7.3" # Not a real version, used to constrain the version we accept.
 fastutil = "8.5.9"
 guava = "31.1-jre"
 jetbrainsAnnotations = "24.0.1"