[Documentation] Enable HTTPS use Custom Certificates (#7508)

### Motivation and context
fix #4767 
my docker-compose.https.yml:
```yaml
# Copyright (C) 2018-2022 Intel Corporation
#
# SPDX-License-Identifier: MIT

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- [x] I have updated the documentation accordingly
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- [x] I have increased versions of npm packages if it is necessary

([cvat-canvas](https://github.com/opencv/cvat/tree/develop/cvat-canvas#versioning),

[cvat-core](https://github.com/opencv/cvat/tree/develop/cvat-core#versioning),

[cvat-data](https://github.com/opencv/cvat/tree/develop/cvat-data#versioning)
and

[cvat-ui](https://github.com/opencv/cvat/tree/develop/cvat-ui#versioning))

### License

- [x] I submit _my code changes_ under the same [MIT License](
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project.
  Feel free to contact the maintainers if that's a concern.


<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

- **New Features**
- Introduced comprehensive documentation for implementing custom SSL
certificates in the CVAT environment.
- Provided step-by-step instructions for setting up and configuring
Traefik to use custom certificates.

- **Documentation**
- Added a new file detailing the process of creating a certificates
directory, modifying Traefik configuration, and starting CVAT with
custom SSL certificates.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Co-authored-by: Andrey Zhavoronkov <[email protected]>

changelog.d/20240919_114257_echowxsy.md

@@ -0,0 +1,4 @@
+### Added
+
+- Added custom certificates documentation 
+  (<https://github.com/cvat-ai/cvat/pull/7508>)

site/content/en/docs/administration/advanced/custom_certificates.md

@@ -0,0 +1,79 @@
+---
+title: 'Custom Certificates'
+linkTitle: 'Custom Certificates'
+description: 'Use Custom Certificates in CVAT'
+weight: 100
+---
+
+CVAT use traefik as a reverse proxy to manage SSL certificates.
+By default, traefik uses Let's Encrypt to generate SSL certificates.
+However, you can use your own certificates instead of Let's Encrypt.
+
+See:
+
+- [Setup Custom Certificates](#setup-custom-certificates)
+- [Create Certificates Directory](#create-certificates-directory)
+- [Change Traefik Configuration](#change-traefik-configuration)
+- [Start CVAT](#start-cvat)
+
+
+## Setup Custom Certificates
+
+### Create Certificates Directory
+
+Create a `certs` directory in the root of the project:
+
+```bash
+mkdir -p ./certs
+
+```
+
+Move your certificates to the `./certs` directory:
+
+```bash
+mv /path/to/cert.pem ./certs/cert.pem
+mv /path/to/key.pem ./certs/key.pem
+```
+
+### Change Traefik Configuration
+
+Create `tls.yml` in the root of the project directory with the following content:
+
+```yaml
+tls:
+  stores:
+    default:
+      defaultCertificate:
+        certFile: /certs/cert.pem
+        keyFile: /certs/key.pem
+```
+
+Edit the `docker-compose.https.yml` file and change the traefik servise configuration as follows:
+
+```yaml
+  traefik:
+    environment:
+      TRAEFIK_ENTRYPOINTS_web_ADDRESS: :80
+      TRAEFIK_ENTRYPOINTS_web_HTTP_REDIRECTIONS_ENTRYPOINT_TO: websecure
+      TRAEFIK_ENTRYPOINTS_web_HTTP_REDIRECTIONS_ENTRYPOINT_SCHEME: https
+      TRAEFIK_ENTRYPOINTS_websecure_ADDRESS: :443
+      # Disable Let's Encrypt
+      # TRAEFIK_CERTIFICATESRESOLVERS_lets-encrypt_ACME_EMAIL: "${ACME_EMAIL:?Please set the ACME_EMAIL env variable}"
+      # TRAEFIK_CERTIFICATESRESOLVERS_lets-encrypt_ACME_TLSCHALLENGE: "true"
+      # TRAEFIK_CERTIFICATESRESOLVERS_lets-encrypt_ACME_STORAGE: /letsencrypt/acme.json
+    ports:
+      - 80:80
+      - 443:443
+    # Add certificates volume and tls.yml rules
+    volumes:
+      - ./certs:/certs
+      - ./tls.yml:/etc/traefik/rules/tls.yml
+```
+
+### Start CVAT
+
+Start CVAT with the following command:
+
+```bash
+docker compose -f docker-compose.yml -f docker-compose.https.yml up -d
+```