Allow integration-testing on archllinux

[CommanderStorm]

Currently, our integrationtest does hardcode the name for ogrmerge.py to be just this.

Some platforms like arch don't follow this and default to ogrmerge for the name https://man.archlinux.org/man/extra/gdal/ogrmerge.1.en

=> on arch, even with gdal package installed, the testcases currently won't work

The file which is causing this trouble is here

martin/tests/test.sh

Lines 30 to 39 in f704001

	# Verify the tools used in the tests are available
	# todo add more verification for other tools like jq file curl sqlite3...
	if [[ $OSTYPE == linux* ]]; then # We only used ogrmerge.py on Linux see the test_pbf() function
	if ! command -v ogrmerge.py > /dev/null; then
	echo "gdal-bin is required for testing"
	echo "For Ubuntu, you could install it with sudo apt update && sudo apt install gdal-bin -y"
	echo "see more at https://gdal.org/en/stable/download.html#binaries"
	exit 1
	fi
	fi

We likely should add a check if ogrmerge is installed instead and use that instead before throwing an error ^^