groovy.lang.GroovyRuntimeException: Failed to parse template script

Jenkins URL: https://foundation.eclipse.org/ci/webdev/job/public/job/www.eclipse.org/job/MR-47/2/console

groovy.lang.GroovyRuntimeException: Failed to parse template script (your template may contain an error or be trying to use expressions not currently supported): startup failed:
SimpleTemplateScript228.groovy: 96: unexpected char: '\' @ line 96, column 16.
     #location ~ /\.ht {

What could be causing this error?

//cc @heurtemattes @mbarbero @oliviergoulet

Edited Dec 05, 2022 by Christopher Guindon

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