Revert "Geos 3.12 (#5350)" (#5359)

.gitignore

environment.yml

gtest

isis/CMakeLists.txt

isis/cmake/FindGeos.cmake

isis/cmake/FindPCL.cmake

isis/src/base/apps/caminfo/CamTools.cpp

isis/src/base/apps/cubediff/main.cpp

isis/src/base/apps/fakecube/main.cpp

isis/src/base/apps/footprintmerge/main.cpp

isis/src/base/objs/Chip/Chip.cpp

isis/src/base/objs/Chip/unitTest.cpp

isis/src/base/objs/EmbreeShapeModel/EmbreeShapeModel.cpp

isis/src/base/objs/GisTopology/GisTopology.cpp

isis/src/base/objs/GisTopology/GisTopology.truth

isis/src/base/objs/GridPolygonSeeder/GridPolygonSeeder.cpp

isis/src/base/objs/GridPolygonSeeder/GridPolygonSeeder.truth

isis/src/base/objs/GridPolygonSeeder/unitTest.cpp

isis/src/base/objs/ImageOverlap/ImageOverlap.truth

isis/src/base/objs/ImageOverlap/unitTest.cpp