Fix indentation in templates

Use Jinja2 lstrip_blocks option in templates to ensure consistent
indentation in generated files.

roles/matrix-nginx-proxy/templates/nginx/conf.d/matrix-dimension.conf.j2

@@ -1,3 +1,4 @@
+#jinja2: lstrip_blocks: "True"
 server {
 	listen {{ 8080 if matrix_nginx_proxy_enabled else 80 }};
 	server_name {{ matrix_nginx_proxy_proxy_dimension_hostname }};

roles/matrix-nginx-proxy/templates/nginx/conf.d/matrix-domain.conf.j2

@@ -1,3 +1,4 @@
+#jinja2: lstrip_blocks: "True"
 server {
 	listen {{ 8080 if matrix_nginx_proxy_enabled else 80 }};
 	server_name {{ matrix_nginx_proxy_base_domain_hostname }};

roles/matrix-nginx-proxy/templates/nginx/conf.d/matrix-riot-web.conf.j2

@@ -1,3 +1,4 @@
+#jinja2: lstrip_blocks: "True"
 server {
 	listen {{ 8080 if matrix_nginx_proxy_enabled else 80 }};
 	server_name {{ matrix_nginx_proxy_proxy_riot_hostname }};

roles/matrix-nginx-proxy/templates/nginx/conf.d/matrix-synapse.conf.j2

@@ -1,3 +1,4 @@
+#jinja2: lstrip_blocks: "True"
 server {
 	listen {{ 8080 if matrix_nginx_proxy_enabled else 80 }};
 	server_name {{ matrix_nginx_proxy_proxy_matrix_hostname }};

roles/matrix-nginx-proxy/templates/nginx/conf.d/nginx-http.conf.j2

@@ -1,3 +1,4 @@
+#jinja2: lstrip_blocks: "True"
 # The default is aligned to the CPU's cache size,
 # which can sometimes be too low to handle our 2 vhosts (Synapse and Riot).
 #

roles/matrix-nginx-proxy/templates/nginx/matrix-synapse-metrics-htpasswd.j2

@@ -1,2 +1,3 @@
+#jinja2: lstrip_blocks: "True"
 # User and password for protecting /_synapse/metrics URI
 prometheus:{{ matrix_nginx_proxy_proxy_synapse_metrics_basic_auth_key }}

roles/matrix-nginx-proxy/templates/nginx/nginx.conf.j2

@@ -1,3 +1,4 @@
+#jinja2: lstrip_blocks: "True"
 # This is a custom nginx configuration file that we use in the container (instead of the default one),
 # because it allows us to run nginx with a non-root user.
 #