tests: bumped the NGINX core to 1.29.2.

Author: zhuizhuhaomeng

.travis.yml

@@ -47,8 +47,7 @@ env:
     - NGX_BUILD_JOBS=$JOBS
     - TEST_NGINX_SLEEP=0.006
   matrix:
-    - NGINX_VERSION=1.21.4
-    - NGINX_VERSION=1.25.3
+    - NGINX_VERSION=1.29.2
 
 install:
   - if [ ! -f download-cache/drizzle7-2011.07.21.tar.gz ]; then wget -P download-cache https://github.com/openresty/openresty-deps-prebuild/releases/download/v20230902/drizzle7-2011.07.21.tar.gz; fi