fix the testsuite for '--enable-quarantine-support' and '--disable-ml' configuration

Author: benoitdudu

tcl/envmngt.tcl.in

@@ -1192,14 +1192,15 @@ end}
       foreach(_mlv ${_mlv_list})
          if(${_mlv} MATCHES "^[A-Za-z_][A-Za-z0-9_]*$")
             if(DEFINED ENV{${_mlv}})
-               set(_mlre "${_mlre}__MODULES_QUAR_${_mlv}=$ENV{${_mlv}};")
+               string(APPEND _mlre " [===[__MODULES_QUAR_${_mlv}=$ENV{${_mlv}}]===]")
             endif()
             set(_mlrv "MODULES_RUNENV_${_mlv}")
-            set(_mlre "${_mlre}${_mlv}=$ENV{${_mlrv}};")
+            string(APPEND _mlre " [===[${_mlv}=$ENV{${_mlrv}}]===]")
         endif()
       endforeach()
       if (NOT "${_mlre}" STREQUAL "")
-         set(_mlre "env;${_mlre}__MODULES_QUARANTINE_SET=1;")
+         string(PREPEND _mlre " [===[env]===]")
+         string(APPEND  _mlre " [===[__MODULES_QUARANTINE_SET=1]===]")
       endif()
    endif()}
          }