Add Go 1.26 to CI flow

Author: aldas

.github/workflows/echo-contrib.yml

@@ -14,7 +14,7 @@ permissions:
 
 env:
   # run coverage and benchmarks only with the latest Go version
-  LATEST_GO_VERSION: "1.25"
+  LATEST_GO_VERSION: "1.26"
 
 jobs:
   test:
@@ -25,7 +25,7 @@ jobs:
         # Echo CORE tests with last four major releases (unless there are pressing vulnerabilities)
         # As we depend on MANY DIFFERENT libraries which of SOME support last 2 Go releases we could have situations when
         # we derive from last four major releases promise.
-        go: ["1.25"]
+        go: ["1.25", "1.26"]
     name: ${{ matrix.os }} @ Go ${{ matrix.go }}
     runs-on: ${{ matrix.os }}
     steps: