Adding Security Workflows to GitHub Actions (2/2): gosec workflow

[AzfaarQureshi]

Motivation

Related to PR #506 and issue open-telemetry/oteps#144

Gosec is a static analysis engine which scans go source code for security vulnerabilities. As the project grows and we near GA it might be useful to have a workflow which checks for security vulnerabilities with every PR so we can ensure every incremental change is following best development practices. Also passing basic security checks will also make sure that there aren't any glaring issues for our users.

Changes

• This PR adds gosec security checks to the repo

Workflow Triggers

• cron job at 1:30am
• workflow_dispatch (in case maintainers want to trigger a security check manually)

cc- @alolita