Add a new pre-commit-hook to automatically add a copyright

[zhouzaida]

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Motivation

Add a new pre-commit-hook to automatically add a copyright.

Modification

Please briefly describe what modification is made in this PR.

BC-breaking (Optional)

Does the modification introduce changes that break the backward-compatibility of the downstream repositories?
If so, please describe how it breaks the compatibility and how the downstream projects should modify their code to keep compatibility with this PR.

Use cases (Optional)

If this PR introduces a new feature, it is better to list some use cases here, and update the documentation.

Checklist

1. Pre-commit or other linting tools are used to fix the potential lint issues.
2. The modification is covered by complete unit tests. If not, please add more unit tests to ensure the correctness.
3. If the modification has a dependency on downstream projects of a newer version, this PR should be tested with all supported versions of downstream projects.
4. The documentation has been modified accordingly, like docstring or example tutorials.

[codecov]

Codecov Report

Merging #166 (f2dcd28) into master (59470fe) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #166   +/-   ##
=======================================
  Coverage   66.79%   66.79%           
=======================================
  Files         188      188           
  Lines        6191     6191           
  Branches      957      957           
=======================================
  Hits         4135     4135           
  Misses       1765     1765           
  Partials      291      291           

Flag	Coverage Δ
unittests	66.79% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...deploy/codebase/mmdet/core/ops/detection_output.py	77.77% <ø> (ø)
mmdeploy/codebase/mmdet/core/ops/prior_box.py	70.00% <ø> (ø)
mmdeploy/codebase/mmdet/models/backbones.py	15.78% <ø> (ø)
...debase/mmdet/models/dense_heads/base_dense_head.py	30.61% <ø> (ø)
mmdeploy/codebase/mmdet/models/necks.py	50.00% <ø> (ø)

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[RunningLeon]

LGTM