fix typo in libFuzzer documentation

Change-Id: I855b81d7cef2353eb272ac918187188f1bb93608
Reviewed-on: https://chromium-review.googlesource.com/974792Reviewed-by: Abhishek Arya <inferno@chromium.org>
Commit-Queue: Abhishek Arya <inferno@chromium.org>
Cr-Commit-Position: refs/heads/master@{#544973}

testing/libfuzzer/getting_started.md

@@ -54,7 +54,7 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
 }
 ```
 
-*Note*: You should create the fuzz target file `<my_fuzzer>.cc next to the code
+*Note*: You should create the fuzz target file `<my_fuzzer>.cc` next to the code
 that is being tested and in the same directory as your other unit tests. Please
 do not use `testing/libfuzzer/fuzzers` directory, this was a directory used for
 initial sample fuzz targets and is no longer recommended for landing new fuzz
@@ -309,4 +309,4 @@ performance and for optimization hints.
 [Build Config]: reference.md#Builder-configurations
 [its own documentation]: http://llvm.org/docs/LibFuzzer.html#output
 [Getting Started with libprotobuf-mutator in Chromium]: libprotobuf-mutator.md
-[base::FuzzedDataProvider]: https://cs.chromium.org/chromium/src/base/test/fuzzed_data_provider.h
\ No newline at end of file
+[base::FuzzedDataProvider]: https://cs.chromium.org/chromium/src/base/test/fuzzed_data_provider.h