Fix typo
### Describe Your Changes
Fix typo in the vmalert docs. In the docs it states rules at `VMAgent`'s
namespace when it should be `VMAlert`'s namespace.
### Checklist
The following checks are **mandatory**:
- [x] My change adheres [VictoriaMetrics contributing
guidelines](https://docs.victoriametrics.com/contributing/).
* docs: remove raw and endraw tags as they are not needed for the new version of site
Signed-off-by: Artem Navoiev <tenmozes@gmail.com>
* revert formating in vmaler
Signed-off-by: Artem Navoiev <tenmozes@gmail.com>
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Signed-off-by: Artem Navoiev <tenmozes@gmail.com>
