imageio: fix coverage build (google#9443)

In order for code coverage to work we need to use
`compile_python_fuzzer` when building the fuzzers

Fixes: google#9442

projects/imageio/build.sh

@@ -19,15 +19,5 @@ python3 setup.py build install
 
 # Build fuzzers in $OUT.
 for fuzzer in $(find . -name 'fuzz_*.py'); do
-  fuzzer_basename=$(basename -s .py $fuzzer)
-  fuzzer_package=${fuzzer_basename}.pkg
-  pyinstaller --distpath $OUT --onefile --name $fuzzer_package $fuzzer
-
-  # Create execution wrapper.
-  echo "#!/bin/sh
-# LLVMFuzzerTestOneInput for fuzzer detection.
-this_dir=\$(dirname \"\$0\")
-ASAN_OPTIONS=\$ASAN_OPTIONS:symbolize=1:external_symbolizer_path=\$this_dir/llvm-symbolizer:detect_leaks=0 \
-\$this_dir/$fuzzer_package \$@" > $OUT/$fuzzer_basename
-  chmod +x $OUT/$fuzzer_basename
+  compile_python_fuzzer $fuzzer
 done