Update docker Docker tag to v26.1.4

This MR contains the following updates:

Package	Type	Update	Change
docker	service-image	patch	26.1.3-dind -> 26.1.4-dind
docker	image	patch	26.1.3 -> 26.1.4

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Configuration

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This MR has been generated by Renovate Bot.

.gitlab-ci.yml

 # This file is a template, and might need editing before it works on your project.
 # Official docker image.
-image: docker:26.1.3
+image: docker:26.1.4
 
 services:
-  - docker:26.1.3-dind
+  - docker:26.1.4-dind
 
 .build-main:
   stage: build