CI: Run fuzzer daily

Update the `fuzz/generate-files.sh` script to mimic that in
`rust-bitcoin` and generate a new fuzz job that runs the fuzz tests
daily for an hour.

Run the fuzz job the time that `rust-bitcoin` fuzz job finishes - I
don't know if that matters. I still don't know if there are org wide
limits or just repo limits but it doesn't hurt to run at a different
time.

Author: tcharding

.github/workflows/fuzz.yml renamed to .github/workflows/cron-daily-fuzz.yml

@@ -1,6 +1,7 @@
 [package]
 name = "descriptor-fuzz"
-edition = "2018"
+edition = "2021"
+rust-version = "1.56.1"
 version = "0.0.1"
 authors = ["Generated by fuzz/generate-files.sh"]
 publish = false

fuzz/Cargo.toml

@@ -11,7 +11,8 @@ source "$REPO_DIR/fuzz/fuzz-util.sh"
 cat > "$REPO_DIR/fuzz/Cargo.toml" <<EOF
 [package]
 name = "descriptor-fuzz"
-edition = "2018"
+edition = "2021"
+rust-version = "1.56.1"
 version = "0.0.1"
 authors = ["Generated by fuzz/generate-files.sh"]
 publish = false
@@ -40,13 +41,13 @@ done
 cat > "$REPO_DIR/.github/workflows/fuzz.yml" <<EOF
 # Automatically generated by fuzz/generate-files.sh
 name: Fuzz
-
 on:
-  push:
-    branches:
-      - master
-      - 'test-ci/**'
-  pull_request:
+  schedule:
+    # 5am every day UTC, this correlates to:
+    # - 11pm PDT
+    # - 7am CET
+    # - 5pm AEDT
+    - cron: '00 06 * * *'
 
 jobs:
   fuzz:
@@ -55,26 +56,26 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
+        # We only get 20 jobs at a time, we probably don't want to go
+        # over that limit with fuzzing because of the hour run time.
         fuzz_target: [
 $(for name in $(listTargetNames); do echo "$name,"; done)
         ]
     steps:
       - name: Install test dependencies
         run: sudo apt-get update -y && sudo apt-get install -y binutils-dev libunwind8-dev libcurl4-openssl-dev libelf-dev libdw-dev cmake gcc libiberty-dev
-      - uses: actions/checkout@v2
-      - uses: actions/cache@v2
+      - uses: actions/checkout@v4
+      - uses: actions/cache@v4
         id: cache-fuzz
         with:
           path: |
             ~/.cargo/bin
             fuzz/target
             target
           key: cache-\${{ matrix.target }}-\${{ hashFiles('**/Cargo.toml','**/Cargo.lock') }}
-      - uses: actions-rs/toolchain@v1
+      - uses: dtolnay/rust-toolchain@stable
         with:
-          toolchain: '1.65'
-          override: true
-          profile: minimal
+          toolchain: '1.65.0'
       - name: fuzz
         run: cd fuzz && ./fuzz.sh "\${{ matrix.fuzz_target }}"
       - run: echo "\${{ matrix.fuzz_target }}" >executed_\${{ matrix.fuzz_target }}