Fix workaround for Proj versions 9.0.0 to 9.4.0

[oshawa-connection]

Hello,

This is a fix for a workaround for a bug in Proj versions between version 9.0.0 and 9.4.0 (inclusive), which is described in this issue:

#7019

The source of this problem was a workaround in mapserver for a bug in proj prior to version 9.4.1. The workaround checks for proj major versions between 6 and 9, and then applies a fix. However, versions 9.0.0 through 9.4.0 suffer from the original proj bug, and do not have the workaround applied.

I'm fairly confident of my change on line 1903, but on line 1909 I had not much idea what I was doing. I only tested requests in EPSG:4326 and EPSG:3857 which the workaround targets, I did not test with expanded projection strings.

I am happy to write some tests + test data for this change if required!