lib: nghttp2: Disable auto-detection for OpenSSL

[cosmo0920]

Even if dusabling the auto-detection for OpenSSL in nghttp2,
I got the following result:

[INPUT]
    Name        http
    Port        8080
    tls         On
    tls.verify  Off
    tls.crt_file self_signed.crt
    tls.key_file self_signed.key

[OUTPUT]
    Name stdout
    Match *

% bin/fluent-bit -c in_http.conf
Fluent Bit v3.0.0
* Copyright (C) 2015-2024 The Fluent Bit Authors
* Fluent Bit is a CNCF sub-project under the umbrella of Fluentd
* https://fluentbit.io

___________.__                        __    __________.__  __          ________  
\_   _____/|  |  __ __   ____   _____/  |_  \______   \__|/  |_  ___  _\_____  \ 
 |    __)  |  | |  |  \_/ __ \ /    \   __\  |    |  _/  \   __\ \  \/ / _(__  < 
 |     \   |  |_|  |  /\  ___/|   |  \  |    |    |   \  ||  |    \   / /       \
 \___  /   |____/____/  \___  >___|  /__|    |______  /__||__|     \_/ /______  /
     \/                     \/     \/               \/                        \/ 

[2024/03/21 19:32:27] [ info] [fluent bit] version=3.0.0, commit=79c05d92fd, pid=9487
[2024/03/21 19:32:27] [ info] [storage] ver=1.5.1, type=memory, sync=normal, checksum=off, max_chunks_up=128
[2024/03/21 19:32:27] [ info] [cmetrics] version=0.7.0
[2024/03/21 19:32:27] [ info] [ctraces ] version=0.4.0
[2024/03/21 19:32:27] [ info] [input:http:http.0] initializing
[2024/03/21 19:32:27] [ info] [input:http:http.0] storage_strategy='memory' (memory only)
[2024/03/21 19:32:27] [ info] [output:stdout:stdout.0] worker #0 started
[2024/03/21 19:32:27] [ info] [sp] stream processor started
[0] http.0: [[1711017151.387275000, {}], {"protocol"=>"http2?"}]
^C[2024/03/21 19:32:33] [engine] caught signal (SIGINT)
[2024/03/21 19:32:33] [ info] [output:stdout:stdout.0] thread worker #0 stopping...
[2024/03/21 19:32:33] [ info] [output:stdout:stdout.0] thread worker #0 stopped

% curl --verbose -XPOST -H 'Content-Type: application/json' -d '{"protocol":"http2?"}' -k https://localhost:8080
Note: Unnecessary use of -X or --request, POST is already inferred.
*   Trying [::1]:8080...
* connect to ::1 port 8080 failed: Connection refused
*   Trying 127.0.0.1:8080...
* Connected to localhost (127.0.0.1) port 8080
* ALPN: curl offers h2,http/1.1
* (304) (OUT), TLS handshake, Client hello (1):
* (304) (IN), TLS handshake, Server hello (2):
* (304) (IN), TLS handshake, Unknown (8):
* (304) (IN), TLS handshake, Certificate (11):
* (304) (IN), TLS handshake, CERT verify (15):
* (304) (IN), TLS handshake, Finished (20):
* (304) (OUT), TLS handshake, Finished (20):
* SSL connection using TLSv1.3 / AEAD-CHACHA20-POLY1305-SHA256
* ALPN: server accepted h2
* Server certificate:
*  subject: CN=test.host.net
*  start date: Mar 21 08:54:55 2024 GMT
*  expire date: Apr 20 08:54:55 2024 GMT
*  issuer: CN=test.host.net
*  SSL certificate verify result: self signed certificate (18), continuing anyway.
* using HTTP/2
* [HTTP/2] [1] OPENED stream for https://localhost:8080/
* [HTTP/2] [1] [:method: POST]
* [HTTP/2] [1] [:scheme: https]
* [HTTP/2] [1] [:authority: localhost:8080]
* [HTTP/2] [1] [:path: /]
* [HTTP/2] [1] [user-agent: curl/8.4.0]
* [HTTP/2] [1] [accept: */*]
* [HTTP/2] [1] [content-type: application/json]
* [HTTP/2] [1] [content-length: 21]
> POST / HTTP/2
> Host: localhost:8080
> User-Agent: curl/8.4.0
> Accept: */*
> Content-Type: application/json
> Content-Length: 21
> 
< HTTP/2 201 
< content-length: 0
< 
* Connection #0 to host localhost left intact

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