feat(docker): collect tool LICENSE files into install dir

[luarss]

Copy LICENSE files from tool source trees into tools/install/licenses/ so they are included in the final image. Excludes tools/OpenROAD/src/sta.

Fixes: https://github.com/The-OpenROAD-Project/AutoTuner/issues/146

Repro:

docker run --rm license-test:latest find /work/install/licenses -type f | sort

Output:

/work/install/licenses/kepler-formal/thirdparty/naja/thirdparty/naja-verilog/LICENSE           
/work/install/licenses/kepler-formal/thirdparty/naja/thirdparty/naja-verilog/LICENSES/Apache-2.0.txt
/work/install/licenses/kepler-formal/thirdparty/naja/thirdparty/naja-verilog/LICENSES/CC0-1.0.txt   
/work/install/licenses/kepler-formal/thirdparty/naja/thirdparty/naja-verilog/thirdparty/googletest/LICENSE
/work/install/licenses/kepler-formal/thirdparty/naja/thirdparty/spdlog-1.17.0/LICENSE                     
/work/install/licenses/kepler-formal/thirdparty/yaml-cpp/LICENSE                                          
/work/install/licenses/kepler-formal/thirdparty/yaml-cpp/test/googletest-1.13.0/LICENSE                   
/work/install/licenses/yosys-slang/LICENSE                                                                
/work/install/licenses/yosys-slang/third_party/fmt/LICENSE                                                
/work/install/licenses/yosys-slang/third_party/slang/LICENSE                                              
/work/install/licenses/yosys-slang/third_party/slang/LICENSES/BSL-1.0.txt                                 
/work/install/licenses/yosys-slang/third_party/slang/LICENSES/MIT.txt                                     
/work/install/licenses/yosys/abc/src/misc/btor/LICENSE.txt                                                
/work/install/licenses/yosys/abc/src/misc/bzlib/LICENSE                                                   
/work/install/licenses/yosys/abc/src/sat/bsat2/LICENSE                                                    
/work/install/licenses/yosys/abc/src/sat/cadical/LICENSE                                                  
/work/install/licenses/yosys/abc/src/sat/kissat/LICENSE                                                   
/work/install/licenses/yosys/abc/src/sat/satoko/LICENSE                                                   
/work/install/licenses/yosys/libs/cxxopts/LICENSE                                                         
/work/install/licenses/yosys/libs/minisat/LICENSE 

[gemini-code-assist]

Code Review

This pull request updates the .dockerignore file to exclude build directories for OpenROAD, yosys-slang, and kepler-formal. It also modifies the Dockerfile.builder to automate the collection of license files from the tools source tree into the installation directory, while excluding specific paths. Feedback was provided to improve the robustness of the license collection script by excluding the destination directory from the search and using IFS= read -r to handle potential spaces in file paths.

[maliberty]

Are you include those from OpenROAD?