AVRO-3242 Add config for TravisCI on Linux ARM64

[martin-g]

Jira

• My PR addresses the following AVRO-3242 issue

Tests

• My PR does not need new tests because it just introduces an additional CI system.

Commits

• My commits all reference Jira issues in their subject lines. In addition, my commits follow the guidelines from "How to write a good git commit message":
  1. Subject is separated from body by a blank line
  2. Subject is limited to 50 characters (not including Jira issue reference)
  3. Subject does not end with a period
  4. Subject uses the imperative mood ("add", not "adding")
  5. Body wraps at 72 characters
  6. Body explains "what" and "why", not "how"

Documentation

• No new functionality