fix: Fix image import related type errors

There have been type errors showing up on some PRs relating to image
imports; TypeScript interprets them as strings, but we have them typed
as `ImageSourcePropType`. The mismatch is there because these image
imports are modified later in the build system.

Normally this is handled by our type declarations, which declare
upfront which types these imports should have. But on some PRs, it
seems that TypeScript will evaluate these declarations too late, after
files including image imports.

I had trouble reproducing this problem on `main`, but it can be seen
in the PR #8828 (commit b027cfa). If
you include this change on that branch, it resolves the problem.

Author: Gudahtt

tsconfig.lint.json

@@ -2,6 +2,7 @@
   "extends": "./tsconfig.json",
   // TODO: Fix type errors and uncomment all directories
   "include": [
+    "app/declarations.d.ts",
     // "app/**/*",
     "app/__mocks__/**/*",
     "app/actions/**/*",
@@ -17,8 +18,7 @@
     "app/reducers/**/*",
     "app/selectors/**/*",
     "app/store/**/*",
-    "app/styles/**/*",
+    "app/styles/**/*"
     // "app/util/**/*",
-    "app/declarations.d.ts"
   ]
 }