Optimize Shader default texture color

[GuoLei1990]

Please check if the PR fulfills these requirements

• [x] The commit message follows our guidelines
• [ ] Tests for the changes have been added (for bug fixes / features)
• [ ] Docs have been added / updated (for bug fixes / features)

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 88.63636% with 5 lines in your changes missing coverage. Please review.

Project coverage is 66.11%. Comparing base (4b28345) to head (3a5ad2d). Report is 13 commits behind head on main.

Files	Patch %	Lines
packages/core/src/shader/ShaderProgram.ts	40.00%	3 Missing :warning:
packages/core/src/BasicResources.ts	94.73%	1 Missing and 1 partial :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #2114 +/- ## ========================================== + Coverage 66.09% 66.11% +0.01% ========================================== Files 460 461 +1 Lines 23013 23061 +48 Branches 3370 3389 +19 ========================================== + Hits 15211 15247 +36 - Misses 6637 6640 +3 - Partials 1165 1174 +9 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.