dev_scripts: Implement two more steps

Implement the following steps from the QA docs:

1. Check if the latest Python version that we support is installed. For
   example, we currently support Python 3.12, so we add code to check
   that the latest Python 3.12.x version is installed.
2. Download the Tesseract data using our script, both on Windows and
   Linux.

dev_scripts/qa.py

@@ -3,14 +3,20 @@
 import abc
 import argparse
 import difflib
+import json
 import logging
 import re
 import selectors
 import subprocess
 import sys
+import urllib.request
+from pathlib import Path
 
 logger = logging.getLogger(__name__)
 
+PYTHON_VERSION = "3.12"
+EOL_PYTHON_URL = "https://endoflife.date/api/python.json"
+
 CONTENT_QA = r"""## QA
 
 To ensure that new releases do not introduce regressions, and support existing
@@ -776,6 +782,10 @@ class QABase(abc.ABC):
                 self.prompt("Does it pass?", choices=["y", "n"])
         logger.info("Successfully completed QA scenarios")
 
+    @task("Download Tesseract data", auto=True)
+    def download_tessdata(self):
+        self.run("python", str(Path("install", "common", "download-tessdata.py")))
+
     @classmethod
     @abc.abstractmethod
     def get_id(cls):
@@ -802,6 +812,40 @@ class QAWindows(QABase):
         while msvcrt.kbhit():
             msvcrt.getch()
 
+    def get_latest_python_release(self):
+        with urllib.request.urlopen(EOL_PYTHON_URL) as f:
+            resp = f.read()
+            releases = json.loads(resp)
+            for release in releases:
+                if release["cycle"] == PYTHON_VERSION:
+                    # Transform the Python version string (e.g., "3.12.7") into a list
+                    # (e.g., [3, 12, 7]), and return it
+                    return [int(num) for num in release["latest"].split(".")]
+
+            raise RuntimeError(
+                f"Could not find a Python release for version {PYTHON_VERSION}"
+            )
+
+    @QABase.task(
+        f"Install the latest version of Python {PYTHON_VERSION}", ref=REF_BUILD
+    )
+    def install_python(self):
+        logger.info("Getting latest Python release")
+        try:
+            latest_version = self.get_latest_python_release()
+        except Exception:
+            logger.error("Could not verify that the latest Python version is installed")
+
+        cur_version = list(sys.version_info[:3])
+        if latest_version > cur_version:
+            self.prompt(
+                f"You need to install the latest Python version ({latest_version})"
+            )
+        elif latest_version == cur_version:
+            logger.info(
+                f"Verified that the latest Python version ({latest_version}) is installed"
+            )
+
     @QABase.task("Install and Run Docker Desktop", ref=REF_BUILD)
     def install_docker(self):
         logger.info("Checking if Docker Desktop is installed and running")
@@ -816,7 +860,7 @@ class QAWindows(QABase):
     )
     def install_poetry(self):
         self.run("python", "-m", "pip", "install", "poetry")
-        self.run("poetry", "install")
+        self.run("poetry", "install", "--sync")
 
     @QABase.task("Build Dangerzone container image", ref=REF_BUILD, auto=True)
     def build_image(self):
@@ -838,9 +882,11 @@ class QAWindows(QABase):
         return "windows"
 
     def start(self):
+        self.install_python()
         self.install_docker()
         self.install_poetry()
         self.build_image()
+        self.download_tessdata()
         self.run_tests()
         self.build_dangerzone_exe()
 
@@ -933,6 +979,7 @@ class QALinux(QABase):
     def start(self):
         self.build_dev_image()
         self.build_container_image()
+        self.download_tessdata()
         self.run_tests()
         self.build_package()
         self.build_qa_image()