bug #1387 Declare svelte and svelte-loader as optional dependencies (stof)

This PR was merged into the main branch.

Discussion
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Declare svelte and svelte-loader as optional dependencies

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Issues        | Fix #1386
| License       | MIT

Version 5.3.0 added the peer dependency declaration but forgot to mark it as optional (while the implementation already treats it as optional)

Commits
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8cf4fd7 Declare svelte and svelte-loader as optional dependencies

Author: Kocal

package.json

@@ -200,6 +200,12 @@
     "stylus-loader": {
       "optional": true
     },
+    "svelte": {
+      "optional": true
+    },
+    "svelte-loader": {
+      "optional": true
+    },
     "ts-loader": {
       "optional": true
     },