* root path for the base domain

* Fix path when running in a container

Co-authored-by: Slavi Pantaleev <slavi@devture.com>

Upgrade certbot (v1.16.0 -> v1.17.0) nginx (1.21.0 -> 1.21.1)

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/1154

According to
https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy,
having both a header and the `<meta>`-tag provided by Element itself is
not a problem. The 2 CSP policies get combined.

https://github.com/vector-im/element-web#configuration-best-practices

It's mildly annoying when trying to execute these scripts while logged
in as a regular user, as the missing execute permissions will hinder
autocompletion even when trying to use with sudo.

These shell scripts don't contain secrets, but may fail when ran by a
regular user. The failure is due to the lack of access to the /matrix
directory, and does not result in any damage.

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/1057

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/1024

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/1061
and https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/1057

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/1057

Not sure if this is beneficial though.

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/1057

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/1058

We may try to capture such calls and return a friendlier response (HTML
or JSON) saying "The Synapse Admin API is not enabled", but that may not
be desirable.

For now, we stick to what "upstream" recommends: "simply
don't proxy these APIs", which should lead to the same kind of 404 that
we have now.
See here: 6660912226/docs/reverse_proxy.md (synapse-administration-endpoints)

Jitsi-meet enabled websockets by default, claiming better reliability.
Matrix-nginx-proxy configuration has been set up according to the
Prosody documentation: https://prosody.im/doc/websocket

Potentially fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/1022

**HSTS Preloading:**
In its strongest and recommended form, the [HSTS policy](https://www.chromium.org/hsts) includes all subdomains, and indicates a willingness to be “preloaded” into browsers:
`Strict-Transport-Security: max-age=31536000; includeSubDomains; preload`

**X-Xss-Protection:**
`1; mode=block` which tells the browser to block the response if it detects an attack rather than sanitising the script.

More Production ready nginx headers for Matrix client element.

- duplicate X-Content-Type-Options
- X-Frame-Options header
- Referrer-Policy [Might consider adding variable]
- Secure flag with cookies
- matrix_grafana_content_security_policy variable for [Content Security Policy](https://grafana.com/docs/grafana/latest/administration/configuration/#content_security_policy)

X-XSS-Protection: 1; mode=block; header, for basic XSS protection in legacy browsers.
X-Content-Type-Options: nosniff header, to disable MIME sniffing