fix(astro): types of override components to optional

[AriPerkkio]

• Related to https://github.com/stackblitz/tutorialkit/pull/375

All keys of components should be optional.

18:30:26.671 | > astro check && astro build
18:30:26.671 |  
18:30:30.516 | ✘ [ERROR] The build was canceled
18:30:30.516 |  
18:30:30.519 | 15:30:30 [types] Generated 1.71s
18:30:30.526 | 15:30:30 [check] Getting diagnostics for Astro files in /opt/buildhome/repo...
18:30:32.992 | astro.config.ts:10:7 - error ts(2741): Property 'HeadTags' is missing in type '{ TopBar: string; }' but required in type 'OverrideComponentsOptions'.
18:30:32.993 |  
18:30:32.993 | 10       components: {
18:30:32.993 | ~~~~~~~~~~
18:30:32.993

[stackblitz[bot]]

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