Fix dockerfile and improve linter and formatter

Fix wrong path in dockerfile.
Add `scss` file extension to "lint-staged" config so that prettier is
used to format `scss` files.
Set `eqeqeq` eslint rule severity to "error". Change all `==` instances in
old server code to `===`

Change-Id: Id0694f37556addc1c0cc05bc19e4e1fd1bd3411b
diff --git a/.eslintrc.cjs b/.eslintrc.cjs
index c9dd776..80d8409 100644
--- a/.eslintrc.cjs
+++ b/.eslintrc.cjs
@@ -78,7 +78,7 @@
     '@typescript-eslint/no-explicit-any': 'off',
     '@typescript-eslint/no-unused-vars': 'off',
     camelcase: 'error',
-    eqeqeq: ['warn', 'smart'],
+    eqeqeq: ['error', 'smart'],
     'header/header': header,
     'no-constant-condition': ['error', { checkLoops: false }],
     'simple-import-sort/exports': 'warn',