fuzz: Bump rustc version

CI is complaining:

 package `regex v1.10.0` cannot be built because it requires rustc 1.65
 or newer, while the currently active rustc version is 1.64.0

Bump rustc to v1.65 in the `generate_files.sh` script and run it.

Author: tcharding

.github/workflows/fuzz.yml

@@ -39,7 +39,7 @@ compile_descriptor,
           key: cache-${{ matrix.target }}-${{ hashFiles('**/Cargo.toml','**/Cargo.lock') }}
       - uses: actions-rs/toolchain@v1
         with:
-          toolchain: 1.64
+          toolchain: '1.65'
           override: true
           profile: minimal
       - name: fuzz

fuzz/generate-files.sh

@@ -72,7 +72,7 @@ $(for name in $(listTargetNames); do echo "$name,"; done)
           key: cache-\${{ matrix.target }}-\${{ hashFiles('**/Cargo.toml','**/Cargo.lock') }}
       - uses: actions-rs/toolchain@v1
         with:
-          toolchain: 1.64
+          toolchain: '1.65'
           override: true
           profile: minimal
       - name: fuzz