fix(deps): bump axios to ^1.15.0 to address CVE-2026-40175 (#2675)

Resolves JSDK-57. All axios versions below 1.15.0 are affected by
CVE-2026-40175 (CVSS 10.0). Bumping the lower bound ensures consumers
are protected without needing npm overrides/resolutions.

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: chasepoirier

package-lock.json

@@ -84,7 +84,7 @@
   "dependencies": {
     "@contentful/content-source-maps": "^0.11.33",
     "@contentful/rich-text-types": "^16.6.1",
-    "axios": "^1.13.5",
+    "axios": "^1.15.0",
     "contentful-resolve-response": "^1.9.4",
     "contentful-sdk-core": "^9.4.4",
     "json-stringify-safe": "^5.0.1",