pamhyr: Add script to run pamhyr under guix shell env.

guix.sh

@@ -0,0 +1,3 @@
+#!/usr/bin/env bash
+
+guix shell --manifest=manifest.scm -- python3 ./src/pamhyr.py

manifest.scm

@@ -15,7 +15,7 @@
 ;; along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 (specifications->manifest
- (list "python-minimal" "python-platformdirs" "python-lxml"
+ (list "python" "python-platformdirs" "python-lxml"
        "python-pyqt@5" "python-pyqt5-sip"
        "python-pyqtgraph" "python-qscintilla"
        "python-numpy" "python-shapely" "python-pyshp"