Describe your environment

linux, gcc 7.3.1, protobuf 26.1, latest opentelemetry-cpp

Steps to reproduce

mkdir otel-cpp-starter
cd otel-cpp-starter
git clone https://github.com/open-telemetry/opentelemetry-cpp.git
cd opentelemetry-cpp
mkdir build
cd build
cmake -DBUILD_TESTING=OFF -DWITH_OTLP_HTTP=ON -DBUILD_SHARED_LIBS=OFF -DWITH_ABSEIL=ON -DCURL_LIBRARY=/BuySide_dev_home/users/procques/libcurl/lib -DCURL_INCLUDE_DIR=/home/libcurl/include -DCMAKE_PREFIX_PATH=/home/abseil/Install -DProtobuf_LIBRARIES=/tmp/protobuf/lib64/libprotobuf.a -DProtobuf_INCLUDE_DIR=/tmp/protobuf/include/ -DProtobuf_PROTOC_EXECUTABLE=/tmp/protobuf/bin/protoc ..

(works; no errors)

cmake --build .

[ 5%] Built target opentelemetry-proto

[ 5%] [Run]: "/tmp/protobuf/bin/protoc" "--proto_path=/home/otel-cpp-starter/opentelemetry-cpp/build/opentelemetry-proto-prefix/src/opentelemetry-proto" "--cpp_out=/home/otel-cpp-starter/opentelemetry-cpp/build/generated/third_party/opentelemetry-proto" "/home/otel-cpp-starter/opentelemetry-cpp/build/opentelemetry-proto-prefix/src/opentelemetry-proto/opentelemetry/proto/common/v1/common.proto" "/home/otel-cpp-starter/opentelemetry-cpp/build/opentelemetry-proto-prefix/src/opentelemetry-proto/opentelemetry/proto/resource/v1/resource.proto" "/home/otel-cpp-starter/opentelemetry-cpp/build/opentelemetry-proto-prefix/src/opentelemetry-proto/opentelemetry/proto/trace/v1/trace.proto" "/home/otel-cpp-starter/opentelemetry-cpp/build/opentelemetry-proto-prefix/src/opentelemetry-proto/opentelemetry/proto/logs/v1/logs.proto" "/home/otel-cpp-starter/opentelemetry-cpp/build/opentelemetry-proto-prefix/src/opentelemetry-proto/opentelemetry/proto/metrics/v1/metrics.proto" "/home/otel-cpp-starter/opentelemetry-cpp/build/opentelemetry-proto-prefix/src/opentelemetry-proto/opentelemetry/proto/profiles/v1experimental/profiles.proto" "/home/otel-cpp-starter/opentelemetry-cpp/build/opentelemetry-proto-prefix/src/opentelemetry-proto/opentelemetry/proto/profiles/v1experimental/pprofextended.proto" "/home/otel-cpp-starter/opentelemetry-cpp/build/opentelemetry-proto-prefix/src/opentelemetry-proto/opentelemetry/proto/collector/trace/v1/trace_service.proto" "/home/otel-cpp-starter/opentelemetry-cpp/build/opentelemetry-proto-prefix/src/opentelemetry-proto/opentelemetry/proto/collector/logs/v1/logs_service.proto" "/home/otel-cpp-starter/opentelemetry-cpp/build/opentelemetry-proto-prefix/src/opentelemetry-proto/opentelemetry/proto/collector/metrics/v1/metrics_service.proto" "/home/otel-cpp-starter/opentelemetry-cpp/build/opentelemetry-proto-prefix/src/opentelemetry-proto/opentelemetry/proto/collector/profiles/v1experimental/profiles_service.proto"

Could not make proto path relative: /home/otel-cpp-starter/opentelemetry-cpp/build/opentelemetry-proto-prefix/src/opentelemetry-proto/opentelemetry/proto/profiles/v1experimental/profiles.proto: No such file or directory

gmake[2]: *** [CMakeFiles/opentelemetry_proto.dir/build.make:74: generated/third_party/opentelemetry-proto/opentelemetry/proto/common/v1/common.pb.h] Error 1

gmake[1]: *** [CMakeFiles/Makefile2:694: CMakeFiles/opentelemetry_proto.dir/all] Error 2

gmake: *** [Makefile:136: all] Error 2

(The directory
/home/otel-cpp-starter/opentelemetry-cpp/build/opentelemetry-proto-prefix/src/opentelemetry-proto/opentelemetry/proto/
exists, but
/home/otel-cpp-starter/opentelemetry-cpp/build/opentelemetry-proto-prefix/src/opentelemetry-proto/opentelemetry/proto/profiles
doesn't exist

What is the expected behavior?
I expected the build to complete and generate opentelemetry libraries, as it does when OTLP HTTP is not enabled.

What is the actual behavior?
The build failed because a command it executed referred to a directory which didn't exist:
Could not make proto path relative: /home/otel-cpp-starter/opentelemetry-cpp/build/opentelemetry-proto-prefix/src/opentelemetry-proto/opentelemetry/proto/profiles/v1experimental/profiles.proto: No such file or directory

Additional context