Update fuzzing README from #3806 (#4107)

lib/fuzz/README.md

@@ -3,7 +3,7 @@ Surrealdb maintains a set of fuzz testing harnesses that are managed by
 [cargo-fuzz](https://github.com/rust-fuzz/cargo-fuzz).
 
 To build and run the fuzzer we will need to;
-- Install a specific version of the nightly compiler
+- Install the nightly compiler
 - Install cargo fuzz
 - Build a fuzz friendly version of surrealdb with our harnesses
 
@@ -14,23 +14,13 @@ version of rustc we can't instrument our fuzz-harnesses with coverage feedback.
 Because of this we need to use some of the more bleeding edge features 
 available in the nightly release. 
 
-Unfortunately for us the nightly release is a little unstable and there
-was a [bug](https://github.com/rust-lang/rust/issues/110475) in the 
-latest version of the nightly compiler that prevents use from compiling
-some of surrealdb's dependencies. To workaround this issue we've carefully
-picked a version of the nightly compiler that works with both cargo-fuzz
-and our dependencies. This version is `nightly-2023-04-21`. To install
-this version we simply need to run;
-
-`rustup install nightly-2023-04-21`
-
 ## Installing cargo-fuzz
 Full details on the different install options are available, in the
 [cargo-fuzz book](https://rust-fuzz.github.io/book/cargo-fuzz/setup.html).
 but for the sake of brevity you can just install the basics with the
 command below.
 
-`cargo +nightly-2023-04-21 install cargo-fuzz`
+`cargo +nightly install cargo-fuzz`
 
 ## Building the fuzzers
 Now that we've install cargo-fuzz we can go ahead and build our fuzzers.
@@ -38,20 +28,20 @@ Now that we've install cargo-fuzz we can go ahead and build our fuzzers.
 cd lib  
 # -O: Optimised build
 # --debug-assertions: Catch common bugs, e.g. integer overflow.
-cargo +nightly-2023-04-21 fuzz build -O --debug-assertions
+cargo +nightly fuzz build -O --debug-assertions
 ````
 
 ## Running the fuzzer
 Now that the fuzzer has successfully built we can actually run them. To
 list the available fuzz harnesses we can use the command.
 ```
-cargo +nightly-2023-04-21 fuzz list
+cargo +nightly fuzz list
 ```
 
 Once we know what fuzzer (in this case fuzz_executor) we want to run we 
 can it using the command;
 ```
-cargo +nightly-2023-04-21 fuzz run -O --debug-assertions fuzz_executor
+cargo +nightly fuzz run -O --debug-assertions fuzz_executor
 ```
 
 The previous command will run the fuzzer in libfuzzer's default mode,
@@ -62,7 +52,7 @@ up we can make use of all cores, and use a dictionary file. e.g.
 #        use nproc to match the number of processors on our local
 #        machine.
 # -dict: Make use the fuzzer specific dictionary file.
-cargo +nightly-2023-04-21 fuzz run -O --debug-assertions \
+cargo +nightly fuzz run -O --debug-assertions \
   fuzz_executor -- -fork=$(nproc) \
   -dict=fuzz/fuzz_targets/fuzz_executor.dict
 ```