T7603: Remove default main-heap-page-size

[natali-rs1985]

Some systems have default page-size 4K and it may cause an error

Thread 0 vpp_main
  base 0x7fe0384f5000, size 1g, locked, unmap-on-destroy, name 'main heap'
    page stats: page-size 4K, total 262144, mapped 14092, not-mapped 248052
      numa 0: 14092 pages, 55.05m bytes
    total: 1023.99M, used: 51.99M, free: 972.01M, trimmable: 972.01M

Change Summary

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Code style update (formatting, renaming)
• Refactoring (no functional changes)
• Other (please describe):

Related Task(s)

• https://vyos.dev/T7603

Related PR(s)

Proposed changes

How to test

Checklist:

• I have read the CONTRIBUTING document
• I have linked this PR to one or more Phabricator Task(s)
• My commit headlines contain a valid Task id
• My change requires a change to the documentation
• I have updated the documentation accordingly