Update go toolchain directive to v1.26.4

Signed-off-by: red-hat-konflux <126015336+red-hat-konflux[bot]@users.noreply.github.com>

Author: red-hat-konflux[bot]

.github/workflows/kuttl-int-tests.yaml

@@ -22,7 +22,7 @@ jobs:
 
     - uses: actions/setup-go@v5
       with:
-        go-version: 1.24.6
+        go-version: 1.26.4
 
     - uses: actions/checkout@v4
 

go.mod

@@ -2,7 +2,7 @@ module github.com/confidential-containers/trustee-operator
 
 go 1.25.0
 
-toolchain go1.25.9
+toolchain go1.26.4
 
 require (
 	github.com/go-logr/logr v1.4.3