unresolved variables in the dast templates

[zerokeeper]

Nuclei version:

v3.2.9

Current Behavior:

unresolved variables: {{FQDN}} {{RDN}}
or unresolved more other variables.

Steps To Reproduce:

use the blind-ssrf.yaml of nuclei-templates.

nuclei -dast -id blind-ssrf -u https://example.com/?url=https://example.com -debug-req

show error:
[WRN] [blind-ssrf] Could not make http request for https://example.com/?url=https://example.com: unresolved variables found: FQDN

Anything else:

Similar to the issue.
#5181