sourcetrail: fix build for python indexer

[midchildan]

Motivation for this change

The sha256 for the python indexer wasn't updated along with the git
revision. The current hash is for commit 0d1246b.

❯ nix run nixpkgs.nix-prefetch-github -c nix-prefetch-github \
    --rev 0d1246be53b37639427fe9959f748dd0fc429c8f \
    CoatiSoftware SourcetrailPythonIndexer
{
    "owner": "CoatiSoftware",
    "repo": "SourcetrailPythonIndexer",
    "rev": "0d1246be53b37639427fe9959f748dd0fc429c8f",
    "sha256": "05hlpd3am029pv1wi6mys3q0ggp64axmg8bdf1fabl9cl9jffscq",
    "fetchSubmodules": true

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS linux)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Determined the impact on package closure size (by running nix path-info -S before and after)
• Ensured that relevant documentation is up to date
• Fits CONTRIBUTING.md.

[midchildan]

Closing in favor of #107533.