BRE-1158 Dockerfiles shared ownership (#460)

## 🎟️ Tracking

[BRE-1158](https://bitwarden.atlassian.net/browse/BRE-1158)
## 📔 Objective

Include AppSec team and BRE dept for repository-level ownership of
Dockerfile, and Dockerfile related, files.<br/>
## 📸 Screenshots

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width images for better display. -->

## ⏰ Reminders before review

- Contributor guidelines followed
- All formatters and local linters executed and passed
- Written new unit and / or integration tests where applicable
- Protected functional changes with optionality (feature flags)
- Used internationalization (i18n) for all UI strings
- CI builds passed
- Communicated to DevOps any deployment requirements
- Updated any necessary documentation (Confluence, contributing docs) or
informed the documentation team

## 🦮 Reviewer guidelines

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- 👍 (`:+1:`) or similar for great changes
- 📝 (`:memo:`) or ℹ️ (`:information_source:`) for notes or general info
- ❓ (`:question:`) for questions
- 🤔 (`:thinking:`) or 💭 (`:thought_balloon:`) for more open inquiry
that's not quite a confirmed issue and could potentially benefit from
discussion
- 🎨 (`:art:`) for suggestions / improvements
- ❌ (`:x:`) or ⚠️ (`:warning:`) for more significant problems or
concerns needing attention
- 🌱 (`:seedling:`) or ♻️ (`:recycle:`) for future improvements or
indications of technical debt
- ⛏ (`:pick:`) for minor or nitpick changes

[BRE-1158]:
https://bitwarden.atlassian.net/browse/BRE-1158?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ

Author: fntyler

.github/CODEOWNERS

@@ -22,3 +22,9 @@ crates/bitwarden-vault/** @bitwarden/team-vault-dev @bitwarden/team-platform-dev
 ## Multiple owners
 .github/workflows/build-* @bitwarden/team-platform-dev
 .github/workflows/version-bump.yml @bitwarden/team-platform-dev
+
+# Docker-related files
+**/Dockerfile @bitwarden/team-appsec @bitwarden/dept-bre
+**/*.dockerignore @bitwarden/team-appsec @bitwarden/dept-bre
+**/entrypoint.sh @bitwarden/team-appsec @bitwarden/dept-bre
+**/docker-compose.yml @bitwarden/team-appsec @bitwarden/dept-bre