Add -std=c++11 to bv_uintah

[biagas]

Fixes builds with compilers whose default is c++17.

Description

See #19526

Type of change

• [X] Bug fix
• ~~[ ] New feature~~
• ~~[ ] Documentation update~~
• ~~[ ] Other~~

How Has This Been Tested?

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Checklist:

• [ ] I have commented my code where applicable.~~
• [ ] I have updated the release notes.~~
• [ ] I have made corresponding changes to the documentation.~~
• [ ] I have added debugging support to my changes.~~
• [ ] I have added tests that prove my fix is effective or that my feature works.~~
• [ ] I have confirmed new and existing unit tests pass locally with my changes.~~
• [ ] I have added new baselines for any new tests to the repo.~~
• [ ] I have NOT made any changes to protocol or public interfaces in an RC branch.~~