refactor: read the fbneo version from version.h

FBNeo bumps src/burn/version.h without tagging: the scraper wrote the
last tag, v1.0.0.02, while the source said 1.0.0.03. It now reads the
header the way the libretro core prints it. The merge no longer writes
core_version: the hashes come from finalburnneo/FBNeo's tip, which the
libretro/FBNeo pin does not name, so the version stays the one
version_basis reads at that pin. A MAME release profile is written with
its version_basis.

tests/test_e2e.py

@@ -4905,7 +4905,8 @@ struct BurnDriver BurnDrvneogeo = {
         rom = next(f for f in result["files"] if f["name"] == "sp-s2.sp1")
         self.assertEqual(rom["crc32"], "newcrc")
         self.assertEqual(rom["system"], "snk-neogeo-mvs")
-        self.assertEqual(result["core_version"], "v1.0.0.03")
+        # The version is the pin's, read through version_basis.
+        self.assertEqual(result["core_version"], "v1.0.0.02")
 
 
     def _load_config(self, platform_name: str) -> dict: