Change Github to GitHub (#315)

apps/www/pages/sponsorware.tsx

               target="_blank"
               rel="noopener noreferrer"
             >
-              sponsor me on Github
+              sponsor me on GitHub
             </a>{' '}
             (at any level) and sign in below.
           </p>
             ) : (
               <>
                 <StyledButton variant="primary" onClick={() => signin('github')}>
-                  {loading ? 'Loading...' : 'Sign in With Github'}
+                  {loading ? 'Loading...' : 'Sign in with GitHub'}
                 </StyledButton>
                 <StyledDetail>Already a sponsor? Just sign in to visit the app.</StyledDetail>
               </>

packages/tldraw/src/components/TopPanel/Menu/Menu.tsx

         <DMDivider dir="ltr" />
         <a href="https://github.com/Tldraw/Tldraw" target="_blank" rel="nofollow">
           <DMItem>
-            Github
+            GitHub
             <SmallIcon>
               <GitHubLogoIcon />
             </SmallIcon>