Update support links (#661)

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https://github.com/SableClient/Sable/blob/dev/CONTRIBUTING.md before
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### Description

<!-- Please include a summary of the change. Please also include
relevant motivation and context. List any dependencies that are required
for this change. -->

Update support buttons to point to https://opencollective.com/sable

#### Type of change

- [ ] 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

### Checklist:

- [ ] 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
- [ ] My changes generate no new warnings

### AI disclosure:

- [ ] Partially AI assisted (clarify which code was AI assisted and
briefly explain what it does).
- [ ] Fully AI generated (explain what all the generated code does in
moderate detail).
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this PR does. -->

Author: 7w1

.changeset/update-donation-links.md

@@ -0,0 +1,5 @@
+---
+default: patch
+---
+
+Updated Support links to point to https://opencollective.com/sable

CONTRIBUTING.md

@@ -7,6 +7,7 @@ All types of contributions are encouraged and valued. Please make sure to read t
 > And if you like the project, but just don't have time to contribute, that's fine. There are other easy ways to support the project and show your appreciation, which we would also be very happy about:
 >
 > - Star the project
+> - [Donate](https://opencollective.com/sable)! ❤️
 > - Talk about it!
 > - Refer this project in your project's readme
 > - Mention the project at local meetups and tell your friends/colleagues

src/app/features/settings/about/About.tsx

@@ -209,7 +209,7 @@ export function About({ requestBack, requestClose }: Readonly<AboutProps>) {
                     </Button>
                     <Button
                       as="a"
-                      href="https://github.com/SableClient/Sable/pulls"
+                      href="https://opencollective.com/sable"
                       rel="noreferrer noopener"
                       target="_blank"
                       variant="Critical"

src/app/pages/client/WelcomePage.tsx

@@ -41,10 +41,9 @@ export function WelcomePage() {
                     Source Code
                   </Text>
                 </Button>
-                {/*
                 <Button
                   as="a"
-                  href="https://github.com/SableClient/Sable"
+                  href="https://opencollective.com/sable"
                   target="_blank"
                   rel="noreferrer noopener"
                   fill="Soft"
@@ -54,7 +53,6 @@ export function WelcomePage() {
                     Support
                   </Text>
                 </Button>
-                */}
               </Box>
             </Box>
             <Box direction="Column" gap="200" alignItems="Center">