Topcom isRegularTriangulation example running out of memory on some s390x builds

From a recent PPA build of the development branch on s390x using Ubuntu 20.04. (The same thing happened in Ubuntu 20.10, but not Ubuntu 18.04 or Ubuntu 21.04, where everything built just fine):

-- making example results for "isRegularTriangulation"                     
 ulimit -c unlimited; ulimit -t 700; ulimit -m 850000; ulimit -s 8192; ulimit -n 512;  cd /tmp/M2-25317-0/1-rundir/; GC_MAXIMUM_HEAP_SIZE=400M "/<<BUILDDIR>>/macaulay2-1.16.99+git202012151651/M2/usr-dist/s390x-Linux-Ubuntu-20.04/bin/M2-binary" -q --int --no-randomize --no-readline --silent --stop --print-width 129 -e 'needsPackage("Topcom", Reload => true, FileName => "/<<BUILDDIR>>/macaulay2-1.16.99+git202012151651/M2/Macaulay2/packages/Topcom.m2")' <"/tmp/M2-25317-0/0_is__Regular__Triangulation.m2" >>"/<<BUILDDIR>>/macaulay2-1.16.99+git202012151651/M2/usr-dist/common/share/doc/Macaulay2/Topcom/example-output/_is__Regular__Triangulation.errors" 2>&1
/<<BUILDDIR>>/macaulay2-1.16.99+git202012151651/M2/usr-dist/common/share/doc/Macaulay2/Topcom/example-output/_is__Regular__Triangulation.errors:0:1: (output file) error: Macaulay2 exited with status code 1
/tmp/M2-25317-0/0_is__Regular__Triangulation.m2:0:1: (input file)
M2: *** Error 1
 -- 763.683 seconds elapsed
 -- storing example results from output file../../../usr-dist/common/share/doc/Macaulay2/Topcom/example-output/_is__Regular__Triangulation.out
 -- warning: missing file /<<BUILDDIR>>/macaulay2-1.16.99+git202012151651/M2/usr-dist/common/share/doc/Macaulay2/Topcom/example-output/_is__Regular__Triangulation.out
../../m2/debugging.m2:20:6:(1):[9]: error: installPackage: 1 error(s) occurred running examples for package Topcom:

_is__Regular__Triangulation.errors
**********************************
         {0,2,4}, {3,4,5}, {1,2,3}}

o2 = {{0, 1, 2}, {1, 3, 5}, {2, 3, 4}, {0, 1, 5}, {0, 2, 4}, {3, 4, 5}, {1, 2, 3}}

o2 : List

i3 : isRegularTriangulation(A,tri)


 *** out of memory trying to allocate 3311714395 bytes, exiting ***

../../m2/installPackage.m2:684:14:(1):[8]: --back trace--
../../m2/methods.m2:119:80:(1):[7]: --back trace--
../../m2/option.m2:16:8:(1):[6]: --back trace--
../../m2/installPackage.m2:568:5:(1):[5]: --back trace--
../../m2/methods.m2:119:80:(1):[4]: --back trace--
../../m2/option.m2:16:8:(1):[3]: --back trace--
currentString:1:1:(3):[2]: --back trace--
Macaulay2/Core/startup.m2.in:563:33:(0):[1]: --back trace--
Macaulay2/Core/startup.m2.in:674:6:(0): --back trace--
make[4]: *** [Makefile:93: /<<BUILDDIR>>/macaulay2-1.16.99+git202012151651/M2/usr-dist/s390x-Linux-Ubuntu-20.04/lib/s390x-linux-gnu/Macaulay2/Topcom/.installed] Error 1

3311714395 bytes?!? That's over 3 gigs! Is this example really that big?

Start with the Topcom package example _is__Regular__Triangulation.m2 and its isRegularTriangulation call, then inspect the package installation command and the linked s390x build logs. Reproduce the example on an affected build if possible and compare it with the successful Ubuntu builds. Done means the example completes without the multi-gigabyte allocation failure on affected s390x builds.