[test] now no timestamp test case covers gsb files

[tangxifan]

Motivate of the pull request

• To address an existing issue. If so, please provide a link to the issue:
• Breaking new feature. If so, please describe details in the description part.

Describe the technical details

What is currently done? (Provide issue link if applicable)

What does this pull request change?

This PR improves in the following aspects:

• Put gsb files under golden output tracking
• Put io location file under golden output tracking

This will help to ensure backward compatibility in #747

Which part of the code base require a change

• VPR
• Tileable routing architecture generator
• OpenFPGA libraries
• FPGA-Verilog
• FPGA-Bitstream
• FPGA-SDC
• FPGA-SPICE
• Flow scripts
• Architecture library
• Cell library
• Documentation
• Regression tests
• Continous Integration (CI) scripts

Impact of the pull request

• Require a change on Quality of Results (QoR)
• Break back-compatibility. If so, please list who may be influenced.