net.openssl: replace SSL_get1_peer_certificate by SSL_get_peer_certificate for OpenBSD

[lcheylus]

OpenBSD uses LibreSSL (OpenSSL fork) by default for libssl/libcrypto. SSL_get1_peer_certificate is not supported by LibreSSL, replace it by SSL_get_peer_certificate.

Fix #24547

---

Tests OK on OpenBSD current/amd64

$ ./v -stats -W -d use_openssl test vlib/net/http/http_test.v
---- Testing... ----
        V  source  code size:      42212 lines,     193393 tokens,    1164711 bytes,   474 types,    33 modules,   221 files
generated  target  code size:      21296 lines,     793237 bytes
compilation took: 1099.270 ms, compilation speed: 38400 vlines/s, cgen threads: 3
running tests in: /home/fox/dev/vlang.git/vlib/net/http/http_test.v
      OK    [1/4]     0.005 ms    NO asserts | main.test_http_get()
      OK    [2/4]     0.005 ms    NO asserts | main.test_http_get_from_vlang_utc_now()
      OK    [3/4]     0.005 ms    NO asserts | main.test_public_servers()
      OK    [4/4]     0.000 ms    NO asserts | main.test_relative_redirects()
     Summary for running V tests in "http_test.v": 0 total. Elapsed time: 0 ms.

 OK    1197.922 ms vlib/net/http/http_test.v
----
Summary for all V _test.v files: 1 passed, 1 total. Elapsed time: 1201 ms, on 1 job. Comptime: 0 ms. Runtime: 1197 ms.

[huly-for-github]

Connected to Huly®: V_0.6-22922

[spytheman]

Excellent work.