Update PetaLibrary Index Page to Reflect Current Allocation Size Maximums

[joyo7507]

Documents affected: https://curc.readthedocs.io/en/latest/petalibrary/index.html

The current wording in the allocation size note on the main index page for PetaLibrary reads as follows:

• Minimum allocation size: 1 TB
• Maximum initial allocation size for new customers, pending availability:
  • 200 TB in Active storage
  • 100 TB in Archive storage (includes "Active+Archive" and "Archive+DR")

This was likely implemented when archive was a tape system and is no longer applicable to the current architecture. Archive allocations now can host the same maximum allocation size as Active. Recommended to update the note to the following:

• Minimum allocation size: 1 TB
• Maximum initial allocation size for new customers, pending availability: 200TB

It may be worth noting that this is the maximum for an allocation but multiple allocations can be created. This may not be necessary but could help prospective users understand they're not limited to 200TB in total, but including this is up to UST's discretion.