[Bug] Invalid program.json results in a compiler panic

[d0cd]

🐛 Bug Report

Test Case

{
  "program": "import_external_from_network.aleo",
  "version": "0.0.0",
  "description": "",
  "license": "MIT",
  "dependencies": [
    {
      "name": "credits.aleo",
      "location": "network"
    }
  ]
}

Error

> leo build
       Leo ⚠️  Attention - This command is deprecated. Use the 'run' command.

thread `main` panicked at utils/retriever/src/program_context/mod.rs:80:31:
ProgramContext network is None
stack backtrace: 
   0: backtrace::capture::Backtrace::new
   1: leo::set_panic_hook::{{closure}}
   2: std::panicking::rust_panic_with_hook
   3: std::panicking::begin_panic_handler::{{closure}}
   4: std::sys_common::backtrace::__rust_end_short_backtrace
   5: _rust_begin_unwind
   6: core::panicking::panic_fmt
   7: core::option::expect_failed
   8: leo_retriever::retriever::Retriever::retrieve
   9: <leo_lang::cli::commands::build::Build as leo_lang::cli::commands::Command>::apply
  10: leo_lang::cli::commands::Command::execute
  11: leo_lang::cli::cli::run_with_args
  12: scoped_tls::ScopedKey<T>::set
  13: leo::main
  14: std::sys_common::backtrace::__rust_begin_short_backtrace
  15: std::rt::lang_start::{{closure}}
  16: std::rt::lang_start_internal
  17: _main

error: internal compiler error: unexpected panic

note: the compiler unexpectedly panicked. this is a bug.

note: we would appreciate a bug report: https://github.com/AleoHQ/leo/issues/new?labels=bug,panic&template=bug.md&title=[Bug]

note: leo-lang 1.11.0 running on Darwin 23.1.0

note: compiler args: leo build

note: compiler flags: CLI { debug: false, quiet: false, command: Build { command: Build { options: BuildOptions { endpoint: "http://api.explorer.aleo.org/v1", non_recursive: false, offline: false, enable_symbol_table_spans: false, enable_initial_symbol_table_snapshot: false, enable_type_checked_symbol_table_snapshot: false, enable_unrolled_symbol_table_snapshot: false, enable_ast_spans: false, enable_dce: false, enable_all_ast_snapshots: false, enable_initial_ast_snapshot: false, enable_unrolled_ast_snapshot: false, enable_ssa_ast_snapshot: false, enable_flattened_ast_snapshot: false, enable_destructured_ast_snapshot: false, enable_inlined_ast_snapshot: false, enable_dce_ast_snapshot: false } } }, path: None, home: None }