Prepare for 4.0.3 release

Author: oguzhanunlu

CHANGELOG

@@ -1,3 +1,9 @@
+Version 4.0.3 (2025-11-05)
+--------------------------
+Refactor CI (#265)
+Upgrade json-schema-validator from 1.0.76 to 1.5.8 (#265)
+Add comprehensive validator error message test suite (#266)
+
 Version 4.0.2 (2025-02-21)
 --------------------------
 Remove entropy from client failures (#262)

README.md

@@ -11,12 +11,12 @@ Iglu Scala Client is used extensively in **[Snowplow][snowplow-repo]** to valida
 
 ## Installation
 
-The latest version of Iglu Scala Client is 4.0.2, which works with Scala 2.12, 2.13, and 3.
+The latest version of Iglu Scala Client is 4.0.3, which works with Scala 2.12, 2.13, and 3.
 
 If you're using SBT, add the following lines to your build file:
 
 ```scala
-val igluClient = "com.snowplowanalytics" %% "iglu-scala-client" % "4.0.2"
+val igluClient = "com.snowplowanalytics" %% "iglu-scala-client" % "4.0.3"
 ```
 
 ## API