Added label_injection to crate_universe annotations

[UebelAndre]

The new label_injection attribute is used to sanitize "apparent labels" used in annotations to "canonical labels". A common example of this is when adding external dependencies to cargo_build_script targets. E.g.

bazel_dep(name = "openssl", version = "3.3.1")

crate = use_extension("@rules_rust//crate_universe:extensions.bzl", "crate")
crate.annotation(
    crate = "openssl-sys",
    build_script_data = [
        "@openssl//:openssl",
    ],
    build_script_env = {
        "OPENSSL_BIN": "$(execpath @openssl//:openssl)",
    },
    label_injection = {
        "@openssl//:openssl": "@openssl//:openssl",
    },
)
crate.from_cargo(
    name = "crates_index",
    cargo_lockfile = "//:Cargo.lock",
    manifests = ["//:Cargo.toml"],
)
use_repo(crate, "crates_index")

Before this change inject_repo would have been needed to get @openssl to resolve in the generated openssl-sys crate. After this, labels are remapped after resolving the canonical label based on the label_injection attribute so that even if the module above is consumed as a transitive dependency, the modules are still usable (because inject_repo is only applied to the root module).