Files in Example Folder are missing in tarballs

[claudiushaag]

Description

In the current release tarballs for v2.8.7, both from the website and github, a few files seem to be missing.

To Reproduce
Build from a tarball instead of the github repo.
In my case, by invoking
cmake -B build -DBUILD_SHARED_LIBS=ON -DP4EST_USE_SYSTEM_SC=ON -DCMAKE_PREFIX_PATH=./sc_installation

Additional information

CMake Error: File $SRC_DIR/example/particles/separt.pl does not exist.
 │ │ CMake Error at example/CMakeLists.txt:58 (configure_file):
 │ │   configure_file Problem configuring file
 │ │ Call Stack (most recent call first):
 │ │   example/CMakeLists.txt:73 (p4est_copy_resource)
 │ │ CMake Error: File $SRC_DIR/example/timings/tsrana.awk does not exist.
 │ │ CMake Error at example/CMakeLists.txt:58 (configure_file):
 │ │   configure_file Problem configuring file
 │ │ Call Stack (most recent call first):
 │ │   example/CMakeLists.txt:79 (p4est_copy_resource)
 │ │ CMake Error: File $SRC_DIR/example/timings/tsrana.sh does not exist.
 │ │ CMake Error at example/CMakeLists.txt:58 (configure_file):
 │ │   configure_file Problem configuring file
 │ │ Call Stack (most recent call first):
 │ │   example/CMakeLists.txt:79 (p4est_copy_resource)
 │ │ CMake Error: File $SRC_DIR/example/timings/perfscript.sh does not exist.
 │ │ CMake Error at example/CMakeLists.txt:58 (configure_file):
 │ │   configure_file Problem configuring file
 │ │ Call Stack (most recent call first):
 │ │   example/CMakeLists.txt:79 (p4est_copy_resource)
 │ │ CMake Error: File $SRC_DIR/example/mesh/conndebug.p8c does not exist.
 │ │ CMake Error at example/CMakeLists.txt:58 (configure_file):
 │ │   configure_file Problem configuring file
 │ │ Call Stack (most recent call first):
 │ │   example/CMakeLists.txt:92 (p4est_copy_resource)