Add to Readme info about include ENV vars in deployment from another file

[dekhtyarev]

Russia edition:

• Использование yaml include с вариативным количеством отступов:

...
    resources:
      requests:
        cpu: {{ requests_cpu }}
        memory: {{ requests_memory }}
      limits:
        cpu: {{ limits_cpu }}
        memory: {{ limits_memory }}
    env:{% macro incvars() %}{% include "env.yaml.j2" with context %}{% endmacro %}
    {{ incvars()|indent(8) }}