Support Conan lockfiles v0.5

[kzantow]

What would you like to be added:
It seems the Conan lockfile format may have changed significantly between v0.4 and v0.5. We should support both versions.

There is a report that generating a Conan lockfile recently using:

conan lock create conanfile.txt --lockfile-out=conan.lock

... results in:

{
    "version": "0.5",
    "requires": [
        "zlib/1.2.13#e377bee636333ae348d51ca90874e353%1682597484.674",
        "openssl/1.0.2u#3049deead466fa2a399aa941e99e2ced%1679427310.657",
        "libcurl/7.85.0#119acfd0fe5cdc29916a348daf813428%1689844599.198",
        "json-c/0.17#f863bad3e5c80dc90679092f67bbd680%1692230941.393"
    ],
    "build_requires": [
        "pkgconf/1.9.3#5da3944c3226f5764374e4b8b4e1d055%1688570267.668",
        "ninja/1.11.1#77587f8c8318662ac8e5a7867eb4be21%1684431244.21",
        "meson/1.0.0#15586c0ac6f682805875ef903dbe7ee2%1673885561.647",
        "m4/1.4.19#c1c4b1ee919e34630bb9b50046253d3c%1676610086.39",
        "libtool/2.4.7#d55a3c2435c19e830fa77aa5c6c19350%1677509454.216",
        "gnu-config/cci.20210814#15c3bf7dfdb743977b84d0321534ad90%1681250000.747",
        "automake/1.16.5#058bda3e21c36c9aa8425daf3c1faf50%1688481772.751",
        "autoconf/2.71#ce232afdcd21d1269419c355375731e6%1688493320.427"
    ],
    "python_requires": []
}

... whereas Syft is expecting a lockfile in a format more in line with this (from the test fixtures):

{
 "graph_lock": {
  "nodes": {
   "0": {
    "ref": "zlib/1.2.12",
    "options": "fPIC=True\nshared=False",
    "requires": [],
    "path": "all/conanfile.py",
    "context": "host"
   }
  },
  "revisions_enabled": false
 },
 "version": "0.4",
 "profile_host": "[settings]\narch=x86_64\narch_build=x86_64\nbuild_type=Release\ncompiler=gcc\ncompiler.libcxx=libstdc++\ncompiler.version=9\nos=Linux\nos_build=Linux\n[options]\n[build_requires]\n[env]\n"
}

Why is this needed:
To support newer Conan lockfiles.