chore: reconcile repo with published v1.2.1

The npm package @jsonresume/schema was published at v1.2.1 (2024-08-06)
but package.json on master still read 1.1.2. semantic-release publishes
and tags from CI without committing the version bump back to the repo,
so the source-of-truth version drifted behind npm.

Verified the only delta between npm v1.2.1 and repo HEAD is the version
string: schema.json, job-schema.json, sample.resume.json, sample.job.json,
validator.js, README.md and LICENSE.md are all byte-identical (SHA256).

This bumps package.json 1.1.2 -> 1.2.1 to match the published artifact.

Refs #522, jsonresume/jsonresume.org#275

Author: Ajax Davis

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@jsonresume/schema",
-  "version": "1.1.2",
+  "version": "1.2.1",
   "description": "JSON Resume Schema",
   "private": false,
   "main": "validator.js",