gh-40688: check for presense of the patch utility
    
some systems might have no `patch` installed, and then the build fails
at the 1st spkg to be patched.
As reported on https://groups.google.com/g/sage-
devel/c/hmIBRrkdecw/m/aQpIcWwXAgAJ


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preview.

### ⌛ Dependencies

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URL: #40688
Reported by: Dima Pasechnik
Reviewer(s): Michael Orlitzky

Author: Release Manager

configure.ac

@@ -220,6 +220,14 @@ then
     AC_MSG_ERROR([Exiting, as the archiver 'ar' can not be found.])
 fi
 
+AC_CHECK_PROG(found_patch, patch, yes, no)
+if test x$found_patch != xyes
+then
+    AC_MSG_NOTICE([Sorry, the 'patch' command must be in the path to build AC_PACKAGE_NAME])
+    AC_MSG_NOTICE([See e.g. https://www.gnu.org/software/patch/])
+    AC_MSG_ERROR([Exiting, as the utility 'patch' can not be found.])
+fi
+
 AC_CHECK_PROG(found_m4, m4, yes, no)
 if test x$found_m4 != xyes
 then