Resource attributes separated from Scope attributes

Follow up for https://github.com/agoda-com/opentelemetry-logs-go/pull/21

# Bug report

## Describe the bug

During log transformation Logger/Exporter Resource Attributes should be as resource attributes and log attributes from instrumentation should be exported as scope attributes

Currently both exporter resource and logger instrumentation resources [merged](https://github.com/coroot/opentelemetry-logs-go/blob/be9c59fab4e63cfbafb0606e7ead4ca8e02bc37b/sdk/logs/logger.go#L43) as scope resources and exported as [Resource Logs](https://github.com/agoda-com/opentelemetry-logs-go/blob/master/exporters/otlp/otlplogs/internal/logstransform/logs.go#L48), however [Exporter](https://github.com/agoda-com/opentelemetry-logs-go/blob/master/exporters/otlp/otlplogs/exporter.go#L77) don't have information about [LoggerProvider](https://github.com/agoda-com/opentelemetry-logs-go/blob/master/sdk/logs/provider.go#L105) resources to separate ResourceLogs from ScopeResources.