Silence meson warning

Commit 619bc23a1a introduced

    WARNING: Project targets '>=0.54' but uses feature introduced in '0.55.0': Passing executable/found program object to script parameter of add_dist_script

Work around that by wrapping the offending line in a meson version check.

Author: Tristan Partin <tristan@neon.tech>
Discussion: https://www.postgresql.org/message-id/flat/D096Q3NFFVH1.1T5RE4MOO9ZFH%40neon.tech

meson.build

@@ -3419,8 +3419,11 @@ alias_target('pgdist', [tar_gz, tar_bz2])
 # But not if we are in a subproject, in case the parent project wants to
 # create a dist using the standard Meson command.
 if not meson.is_subproject()
+  # We can only pass the identifier perl here when we depend on >= 0.55
+  if meson.version().version_compare('>=0.55')
     meson.add_dist_script(perl, '-e', 'exit 1')
   endif
+endif