regress failure on PostGIS 3.1 geos 3.10 head

[robe]

PostgreSQL 14beta1 (very close to beta2) on x86_64-w64-mingw32, compiled by gcc.exe (x86_64-posix-seh-rev0, Built by MinGW-W64 project) 8.1.0, 64-bit
  Postgis 3.1.3dev - (3.1.1-39-g70df06bdf) - 2021-07-01 23:16:37
  scripts 3.1.3dev 3.1.1-39-g70df06bdf
  raster scripts 3.1.3dev 3.1.1-39-g70df06bdf
  GEOS: 3.10.0dev-CAPI-1.15.0
  PROJ: 7.1.1
  SFCGAL: 1.3.8
  GDAL: GDAL 3.2.3, released 2021/04/27

--- ./regress/core/tickets_expected     2021-07-01 18:12:50.435346900 -0400
+++ /projects/postgis/tmp/3.1.3dev_pg14_geos3.10_gdal3.2.0w64/test_75_out      2021-07-01 19:24:22.244759900 -0400
@@ -30,7 +30,7 @@
 #157|ST_Polygon|POLYGON
 #157|ST_CurvePolygon|CURVEPOLYGON
 #157|ST_CircularString|CIRCULARSTRING
-#168|3|MULTIPOLYGON ZM (((4275341.969778511 259186.96699306098 1323.762958283311 -1.797693134862316e+308,4275341.969778511 259186.96699306098 1323.762958283311 -1.797693134862316e+308,4275341.969778511 259186.96699306098 1323.762958283311 -1.797693134862316e+308)))|IllegalArgumentException: Invalid number of points in LinearRing found 3 - must be 0 or >= 4
+#168|3|MULTIPOLYGON ZM (((4275341.969778511 259186.96699306098 1323.762958283311 -1.797693134862316e+308,4275341.969778511 259186.96699306098 1323.762958283311 -1.797693134862316e+308,4275341.969778511 259186.96699306098 1323.762958283311 -1.797693134862316e+308)))|Too few points in geometry component[4275341.96977851 259186.966993061 1323.76295828331]
 #175|SRID=26915;POINT(482020 4984378)
 #178a|0
 #178b|5

I suspect this is a GEOS 3.10 issue

[robe]

In prep for 3.1.3 release

[pramsey]

I'm not seeing this with stable-3.1 and GEOS main.

[robe]

I'm not seeing this anymore either — having debbie test to make sure. I'll reopen if I see blood.