Add CI for Java 26

Closes gh-49189

Author: wilkinsona

.github/workflows/ci.yml

@@ -25,6 +25,9 @@ jobs:
             toolchain: true
           - version: 25
             toolchain: false
+          - version: 26
+            toolchain: true
+            early-access: true
         exclude:
           - os:
               name: Linux