feat(analyzer): move compute_md5 to shared library

shared/libretime_shared/files.py

@@ -0,0 +1,17 @@
+import hashlib
+from pathlib import Path
+
+
+def compute_md5(filepath: Path) -> str:
+    """
+    Compute a file md5sum.
+    """
+    with filepath.open("rb") as file:
+        buffer = hashlib.md5()  # nosec
+        while True:
+            blob = file.read(8192)
+            if not blob:
+                break
+            buffer.update(blob)
+
+        return buffer.hexdigest()