support: accept resource attribute values not limited to string type in OTEL

[meetzaveri]

Is your proposal related to a problem?

In OpenTelemetry integration, Hasura currently only supports string-valued attributes for Resource attributes

Describe the solution you'd like

Ability to define values for Resource attributes, which are not only limited to string. For example, if I want to set version number which is typically in float type which would be passed as value from env var.