fix: docker/Dockerfile to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-DEBIAN12-ZLIB-6008963
- https://snyk.io/vuln/SNYK-DEBIAN12-GLIBC-1547135
- https://snyk.io/vuln/SNYK-DEBIAN12-GLIBC-1547196
- https://snyk.io/vuln/SNYK-DEBIAN12-GLIBC-1547293
- https://snyk.io/vuln/SNYK-DEBIAN12-GLIBC-1547373

docker/Dockerfile

@@ -1,4 +1,4 @@
-FROM python:3.10-slim
+FROM python:3.14.0a3-slim
 LABEL description.short="STAC Populator"
 LABEL description.long="Utility to populate STAC Catalog, Collections and Items from various dataset/catalog sources."
 LABEL maintainer="Francis Charette-Migneault <[email protected]>"