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Description

Currently it is possible to specify name of unknownTemplate in rules configuration file. The issue is that unknown template name are parsed and assigned (bosun/conf/rule/rule.go line 195) but never actually used in code. As a result only static internal template are used.

Fixes #2446 (fill in)
#2446

Type of change

From the following, please check the options that are relevant.

• [X ] Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How has this been tested?

Currently running in our internal environment.

Checklist:

• This contribution follows the project's code of conduct
• This contribution follows the project's contributing guidelines
• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules