[feat]: add support for configuring the VPC interface

[eljohnson92]

What this PR does / why we need it:
This PR supports customizing the VPC interface with 1:1 NAT or public interface settings through providing an explicit VPC interface on the LinodeMachine such as

---
apiVersion: infrastructure.cluster.x-k8s.io/v1alpha2
kind: LinodeMachineTemplate
metadata:
  name: test-cluster-md-0
  namespace: default
spec:
  template:
    spec:
      image: linode/ubuntu22.04
      interfaces:
      - purpose: vpc
        primary: false
      - purpose: public
        primary: true
    

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

Special notes for your reviewer:

TODOs:

• squashed commits
• includes documentation
• adds unit tests
• adds or updates e2e tests

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 65.55%. Comparing base (708b0ac) to head (d511370).
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #518      +/-   ##
==========================================
+ Coverage   65.08%   65.55%   +0.46%     
==========================================
  Files          77       77              
  Lines        3990     4003      +13     
==========================================
+ Hits         2597     2624      +27     
+ Misses       1163     1143      -20     
- Partials      230      236       +6     

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[rahulait]

The change looks good to me. Should we also add some documentation related to it just in case someone else is interested in using such settings?

[rahulait]

lgtm