fix typos

CONTRIBUTING.md

@@ -27,7 +27,7 @@ The frontend code build into "dist" directory. The server (express.js) exposes t
 
 ## Can I create a pull request for Uptime Kuma?
 
-Yes or no, it depends on what you will try to do. Since I don't want to waste your time, be sure to **create empty draft pull request or open an issue, so we can discuss first**. Especially for a large pull request or you don't know it will be merged or not.
+Yes or no, it depends on what you will try to do. Since I don't want to waste your time, be sure to **create an empty draft pull request or open an issue, so we can discuss first**. Especially for a large pull request or you don't know it will be merged or not.
 
 Here are some references:
 
@@ -48,7 +48,7 @@ Here are some references:
 - UI/UX is not close to Uptime Kuma 
 - Existing logic is completely modified or deleted for no reason
 - A function that is completely out of scope
-- Unnesscary large code changes (Hard to review, casuse code conflicts to other pull requests)
+- Unnecessary large code changes (Hard to review, causes code conflicts to other pull requests)
 
 I will mark your pull request in the [milestones](https://github.com/louislam/uptime-kuma/milestones), if I am plan to review and merge it.
 
@@ -183,7 +183,7 @@ By default, the Chromium window will be shown up during the test. Specifying `HE
 
 ## Dependencies
 
-Both frontend and backend share the same package.json. However, the frontend dependencies are eventually not be used in production environment, because it is usually also baked into dist files. So:
+Both frontend and backend share the same package.json. However, the frontend dependencies are eventually not used in the production environment, because it is usually also baked into dist files. So:
 
 - Frontend dependencies = "devDependencies"
   - Examples: vue, chart.js