move bitcoin/fuzz into repo root; add to workspace

This allows testing the fuzztests and making sure that they compile and
tests pass, etc., just using `cargo test --all` in the root.

Cargo.toml

@@ -1,5 +1,8 @@
 [workspace]
-members = ["bitcoin", "hashes", "internals"]
+members = ["bitcoin", "hashes", "internals", "fuzz"]
+
+[patch.crates-io.bitcoin]
+path = "bitcoin"
 
 [patch.crates-io.bitcoin_hashes]
 path = "hashes"

fuzz/Cargo.toml

@@ -14,11 +14,7 @@ honggfuzz_fuzz = ["honggfuzz"]
 [dependencies]
 honggfuzz = { version = "0.5", optional = true, default-features = false }
 afl = { version = "0.4", optional = true }
-bitcoin = { path = "../" }
+bitcoin = { version = "0.30.0" }
-
-# Prevent this from interfering with workspaces
-[workspace]
-members = ["."]
 
 [[bin]]
 name = "deserialize_block"