chore: fix duplicate errors.ts (#2448)

Duplicate "if" in error message description.

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---

## PR-Codex overview
This PR focuses on improving documentation clarity and correcting a
comment in the codebase.

### Detailed summary
- Updated the wording in `monitoring.md` to change "writeable" to
"writable".
- Corrected a comment in `errors.ts` by removing the redundant "if" in
"if if error message".

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question}`

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apps/hubble/www/docs/intro/monitoring.md

@@ -30,4 +30,4 @@ yarn start --statsd-metrics-server 127.0.0.1:8125
 
 ## Troubleshooting
 
-- Make sure that the `grafana/data` directory is writeable to all users. 
+- Make sure that the `grafana/data` directory is writable to all users. 

packages/core/src/errors.ts

@@ -23,7 +23,7 @@ export class HubError extends Error {
   /* Hub classification of error types */
   public readonly errCode: HubErrorCode;
 
-  /* Indicates if if error message can be presented to the user */
+  /* Indicates if error message can be presented to the user */
   public readonly presentable: boolean = false;
 
   /**