Improve logs for Mattermost Push Proxy

Description

We have the Mattermost Push proxy deployed on Kubernetes to serve the community server.
Checking the pod/logs we cannot see any logs generated by the application.

This ticket is about improving the logging for push proxy and uses the structured logging similar we have for mattermost server.

The code for the Mattermost Push Proxy is here https://github.com/mattermost/mattermost-push-proxy. It's purpose is to be the relay between Mattermost servers and the Apple/Google push notification services.

QA Test Steps

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Reporter

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Mana

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Assignee

Unassigned

QA Assignee

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Reporter

Carlos Panato

Epic Link

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Fix versions

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Mattermost Team

Cloud

Sprint

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Labels

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QA Testing Areas

Notifications - Push

GitHub Issue

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Components

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Configure