docker: Downgrade PDAL to 2.7.1 in ubuntu_wxgui (OSGeo#3946)

When building the image, only PROJ 8.2.1 is available, and PDAL 2.7.2 checks for PROJ 9.0+. Reverting until the Dockerfile is modified to include PROJ 9.0+

docker/ubuntu_wxgui/Dockerfile

@@ -226,6 +226,7 @@ ENV DEBIAN_FRONTEND noninteractive
 <<<<<<< HEAD
 <<<<<<< HEAD
 <<<<<<< HEAD
+<<<<<<< HEAD
 ARG PDAL_VERSION=2.4.3
 =======
 <<<<<<< HEAD
@@ -367,6 +368,9 @@ ARG PDAL_VERSION=2.7.1
 =======
 ARG PDAL_VERSION=2.7.2
 >>>>>>> 9e87f51dd7 (CI(deps): Update dependency PDAL/PDAL to v2.7.2 (#3937))
+=======
+ARG PDAL_VERSION=2.7.1
+>>>>>>> 7a1c8d97ba (docker: Downgrade PDAL to 2.7.1 in ubuntu_wxgui (#3946))
 
 SHELL ["/bin/bash", "-c"]