aconfig: Use LazyLock rather than lazy_static

Now that we have Rust 1.80 LazyLock is available in the standard library
so we no longer need to use external crates such as lazy_static.

Bug: 364211748
Test: atest aconfig.test
Test: atest aconfig.prod_mode.test.rust
Test: atest aconfig.test_mode.test.rust
Test: atest aconfig.force_read_only_mode.test.rust
Change-Id: If2862eaf20065c118daa9fc51e9fb403b99dada3