use version when specifying dependency

Fixes: #5

Signed-off-by: Andreea Florescu <[email protected]>

Author: andreeaflorescu

Cargo.toml

@@ -22,7 +22,7 @@ vm-memory = ">=0.2.0"
 
 [dev-dependencies]
 criterion = "=0.3.0"
-vm-memory = {features = ["backend-mmap"]}
+vm-memory = { version = ">=0.2.0", features = ["backend-mmap"] }
 
 [[bench]]
 name = "main"