chore: code sanity ++

- remove useless axios devDep
- Expression 'customPayload' always passes null check at this point
because it is already checked at line 30 (in postToChevereto)

package.json

@@ -39,7 +39,6 @@
     "@types/node": "^14.0.27",
     "@typescript-eslint/eslint-plugin": "^5.26.0",
     "@typescript-eslint/parser": "^5.26.0",
-    "axios": "^0.21.4",
     "babel-jest": "^28.1.0",
     "dotenv": "^8.2.0",
     "eslint": "^8.16.0",

src/postToChevereto.ts

@@ -28,7 +28,7 @@ export const postToChevereto = (params: IPostParams) =>
 
     // Throw instantly when 'txt' or 'redirect' is passed to customPayload.format.. We don't do that here
     if (customPayload) {
-      if (customPayload?.format === "txt" || customPayload?.format === "redirect") {
+      if (customPayload.format === "txt" || customPayload.format === "redirect") {
         throw new Error(
           "'options.customPayload.format' standard alternatives to 'json' are not supported; see USE_WITH_CHEVERETO.md for more details.",
         );