New docs: Convert inline example code to use codeinclude macro

[rnorth]

Improvement for the new mkdocs-based documentation.

Aim to replace the majority of inline code blocks in the docs with codeinclude macros, so that our examples are compiled and tested as part of the build.

This doesn't need to all be done in one PR - it probably ought to be split.

Pages that would benefit from this (in no particular order):

• docs/features/container_logs.md
• docs/features/commands.md
• docs/features/creating_container.md
• docs/features/creating_images.md
• docs/features/files.md
• docs/modules/docker_compose.md
• docs/modules/elasticsearch.md
• docs/modules/kafka.md
• docs/modules/vault.md
• docs/modules/webdriver_containers.md
• docs/test_framework_integration/junit_4.md
• docs/test_framework_integration/junit_5.md
• docs/test_framework_integration/spock.md
• docs/supported_docker_environment/logging_config.md

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. If you believe this is a mistake, please reply to this comment to keep it open. If there isn't one already, a PR to fix or at least reproduce the problem in a test case will always help us get back on track to tackle this.