build: remove compile_mjml script, no python!

if I had taken a second to actually read the documentation, i'd have
    realized the mjml command can process a bunch of files at once.
    On my machine, cuts time down from ~800ms to ~500ms.
While there are still some scripts using python, none are needed to
build the software anymore, so no python build deps!

scripts/compile_mjml.py

@@ -1,52 +0,0 @@
-import subprocess
-import shutil
-import os
-import argparse
-from pathlib import Path
-from multiprocessing import Process
-
-parser = argparse.ArgumentParser()
-parser.add_argument("-o", "--output", help="output directory for .html and .txt files")
-
-args = parser.parse_args()
-
-def runcmd(cmd):
-    if os.name == "nt":
-        return subprocess.check_output(cmd, shell=True)
-    with subprocess.Popen(cmd.split(), stdout=subprocess.PIPE) as proc:
-        return proc.communicate()
-
-def compile(mjml: Path):
-    fname = mjml.with_suffix(".html")
-    runcmd(f"npx mjml {str(mjml)} -o {str(fname)}")
-    if fname.is_file():
-        print(f"Compiled {mjml.name}")
-
-local_path = Path("mail")
-
-threads = []
-
-for mjml in [f for f in local_path.iterdir() if f.is_file() and "mjml" in f.suffix]:
-    p = Process(target=compile, args=(mjml,))
-    p.start()
-    threads.append(p)
-
-for thread in threads:
-    thread.join()
-
-html = [f for f in local_path.iterdir() if f.is_file() and "html" in f.suffix]
-
-output = Path(args.output)  # local_path.parent / "build" / "data"
-output.mkdir(parents=True, exist_ok=True)
-
-for f in html:
-    shutil.copy(str(f), str(output / f.name))
-    print(f"Copied {f.name} to {str(output / f.name)}")
-    txtfile = f.with_suffix(".txt")
-    if txtfile.is_file():
-        shutil.copy(str(txtfile), str(output / txtfile.name))
-        print(f"Copied {txtfile.name} to {str(output / txtfile.name)}")
-    else:
-        print(
-            f"Warning: {txtfile.name} does not exist. Text versions of emails should be supplied."
-        )