gh-40568: fixes in spkg-configure.m4's
    
This allows external flint 3.3.*, and fixes errors in spkg-configure.4
of roman_numerals_py


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### ⌛ Dependencies

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URL: #40568
Reported by: Dima Pasechnik
Reviewer(s): Dima Pasechnik, François Bissey

Author: Release Manager

build/pkgs/flint/spkg-configure.m4

@@ -3,12 +3,12 @@ SAGE_SPKG_CONFIGURE([flint], [
         AC_CHECK_HEADERS([flint/flint.h flint/padic.h], [dnl
           dnl gr_get_fexpr appears in Flint 3.0
           AC_SEARCH_LIBS([gr_get_fexpr], [flint], [dnl
-            dnl Assume Flint 3.3 is too new
-            AC_MSG_CHECKING([whether FLINT version is >= 3.3.0])
+            dnl Assume Flint 3.4 is too new
+            AC_MSG_CHECKING([whether FLINT version is >= 3.4.0])
             AC_COMPILE_IFELSE([dnl
               AC_LANG_PROGRAM([[#include <flint/flint.h>
-                                #if __FLINT_RELEASE >= 30300
-                                # error "FLINT 3.3 is too new"
+                                #if __FLINT_RELEASE > 30399
+                                # error "FLINT 3.4 is too new"
                                 #endif
                               ]])
             ], [dnl