chore: update reference go to v1.26.3 in CI pipelines

Author: karel-rehor

.circleci/config.yml

@@ -2,7 +2,7 @@ version: 2.1
 executors:
   cross-builder:
     docker:
-      - image: quay.io/influxdb/cross-builder:go1.25.9-latest
+      - image: quay.io/influxdb/cross-builder:go1.26.3-latest
     resource_class: large
     environment:
       GOPATH: /root/go

.github/workflows/chronograf-cypress-tests.yaml

@@ -27,7 +27,7 @@ jobs:
       - name: Setup Go
         uses: actions/setup-go@v2
         with:
-          go-version: '1.25.9'
+          go-version: '1.26.3'
 
       - name: Install pkg-config
         run: go install github.com/influxdata/pkg-config@v0.3.0