xds_end2end_test fail with OpenSSL

### What version of gRPC and what language are you using?
v1.68.2

### What operating system (Linux, Windows,...) and version?
Ubuntu 22.04.5

### What runtime / compiler are you using (e.g. python version or version of gcc)
gcc version 11.4.0

### What did you do?
Hi Team,
We are working on building and testing grpc from source using openssl instead of borinngssl using CMake
I was able to build grpc using CMake, but noticed the follwoing test failure for xds_end2end_test.

### What did you expect to see?
Test passing successfully.

### What did you see instead?
Faced the following test failure:
```
/grpc/test/cpp/end2end/xds/xds_end2end_test.cc:1118: Failure
Value of: status.error_message()
Expected: matches regular expression "failed to connect to all addresses; last error: (UNKNOWN|UNAVAILABLE): (ipv6:%5B::1%5D|ipv4:127.0.0.1):[0-9]+: (Failed
to connect to remote host: )?Tls handshake failed \\(TSI_PROTOCOL_FAILURE\\): SSL_ERROR_SSL: error:1000007d:SSL routines:OPENSSL_internal:CERTIFICATE_VERIFY_FAILED(: .*)?"
Actual: "failed to connect to all addresses; last error: UNKNOWN: ipv4:127.0.0.1:2832: Tls handshake failed (TSI_PROTOCOL_FAILURE): SSL_ERROR_SSL: error:0A000086:SSL routines::certificate verify failed: self-signed certificate"

```
Attaching detailed logs below.
Any pointers regarding this will be helpful.Thank you.
[logs_grpc_x86.txt](https://github.com/user-attachments/files/18089882/logs_grpc_x86.txt)

### Anything else we should know about your project / environment?