xray_catalog_labels: maximum name limited to 15 characters

[bmanuel]

Describe the bug
The maximum length of a label name in the provider is set to 15, but the UI shows that the maximum length is 100.

Requirements for and issue

• A fully functioning terraform snippet that can be copy&pasted (no outside files or ENV vars unless that's part of the issue)
• Your version of Artifactory and Xray (you can curl Artifactory version at $host/artifactory/api/system/version and Xray version at
  $host/xray/api/v1/system/version
• Your version of terraform
• Your version of terraform provider
• Your product license (E+/E/Pro)
• Is your Xray Cloud or Self-Hosted
• JFrog support reference (if already raised with support team)

Expected behavior
The resource should allow up to 100 characters

Additional context

terraform-provider-xray/pkg/xray/resource/catalog.go

Line 11 in 4c7668f

MaxLabelNameLength = 15 // User requirement: max 15 characters