fix created new TLS certs with longer key lengths

[seriousme]

On ChromeOS 84 npm test fails immediately after the linter pretest with:

_tls_common.js:135
      c.context.setCert(cert);
                ^

Error: error:140AB18F:SSL routines:SSL_CTX_use_certificate:ee key too small

This PR fixes that by providing a new self-signed TLS cert + private key for testing with the following properties:

• RSA Public-Key: 2048 bit (was 1024bit)
• Signature Algorithm: sha256WithRSAEncryption (was sha1WithRSAEncryption)
• Validity Not After: Aug 20 18:07:06 2030 (was Jun 10 10:03:03 2024 GMT)

A full openssl text dump of the cert can be found below,the command used to create this is:
openssl req -x509 -sha256 -nodes -days 3650 -newkey rsa:2048 -keyout tls-key.pem -out tls-cert.pem -subj "/C=AU/ST=Some-State/O=Internet Widgits Pty Ltd/CN=localhost"

Btw: the certificate signing request (tls-csr.pem) is not required so I removed that.

Kind regards,
Hans

Certificate:
    Data:
        Version: 3 (0x2)
        Serial Number:
            2a:ad:f9:24:2c:28:7d:04:57:8a:b9:fd:5a:e5:1c:8c:d8:c6:b7:93
        Signature Algorithm: sha256WithRSAEncryption
        Issuer: C = AU, ST = Some-State, O = Internet Widgits Pty Ltd, CN = localhost
        Validity
            Not Before: Aug 22 18:07:06 2020 GMT
            Not After : Aug 20 18:07:06 2030 GMT
        Subject: C = AU, ST = Some-State, O = Internet Widgits Pty Ltd, CN = localhost
        Subject Public Key Info:
            Public Key Algorithm: rsaEncryption
                RSA Public-Key: (2048 bit)
                Modulus:
                    00:ad:38:1c:a0:d0:b7:81:5d:72:23:03:09:de:07:
                    90:08:ed:62:18:be:c4:e0:6c:22:18:be:a1:f8:4c:
                    8f:53:4d:75:c3:96:c0:1f:df:90:7e:d1:b2:f1:76:
                    8d:8d:32:56:32:ee:84:fa:d1:5f:e6:bf:80:58:4d:
                    f5:e2:cd:10:25:ce:cd:b1:f4:a9:cb:c2:c0:4d:c5:
                    1c:fd:9d:d7:97:24:e4:1c:df:48:31:27:27:46:69:
                    3e:27:a1:55:a6:bb:e2:d3:a0:1b:eb:82:d6:c8:81:
                    8b:77:d0:c2:d7:db:5a:c3:bc:45:d0:43:b7:d6:30:
                    38:d5:5a:ec:de:af:3c:8f:38:c7:f5:4e:b2:60:c8:
                    70:18:07:c0:3e:0e:4b:e5:fd:10:d6:12:33:e7:59:
                    a0:2d:ba:93:e7:36:ce:13:98:77:6a:16:5c:7e:6c:
                    9e:47:9f:94:8d:b4:b6:2e:e2:01:7a:6d:45:34:f6:
                    30:c9:40:20:8c:af:40:26:27:9b:e1:65:6b:46:07:
                    e0:22:f2:84:b1:94:1b:62:d9:6d:7f:d4:df:58:0c:
                    55:1c:95:48:0b:48:2e:f8:38:66:8b:a2:48:e8:d6:
                    d9:67:59:e0:60:58:c9:b9:8f:75:30:df:d9:bb:6d:
                    cd:5b:98:93:48:4f:74:c7:98:98:26:04:20:d2:8b:
                    79:fd
                Exponent: 65537 (0x10001)
    X509v3 extensions:
            X509v3 Subject Key Identifier: 
                34:8D:21:67:E4:35:BE:D7:AF:EA:38:DD:91:84:CD:38:9F:51:ED:30
            X509v3 Authority Key Identifier: 
                keyid:34:8D:21:67:E4:35:BE:D7:AF:EA:38:DD:91:84:CD:38:9F:51:ED:30

            X509v3 Basic Constraints: critical
                CA:TRUE
    Signature Algorithm: sha256WithRSAEncryption
         72:5b:a5:38:52:44:ef:34:a8:60:6d:13:17:63:d2:73:7c:87:
         75:56:20:2f:a3:09:9d:27:f5:ad:34:32:80:ee:17:14:83:dd:
         c6:51:ed:62:25:9e:10:d0:f3:73:77:6b:17:6a:7c:a9:19:36:
         9e:27:6f:bb:1c:f2:0c:9f:4b:f8:af:37:26:5d:90:0b:8d:38:
         b8:3f:9b:1e:5f:cd:f4:ce:6a:17:e8:59:1c:be:a9:7e:e3:0a:
         bf:75:19:53:13:ed:d9:b0:d6:b7:39:7d:eb:09:a0:5c:04:82:
         f9:1e:00:15:be:78:5e:34:6e:47:00:a0:f2:8e:d4:fc:82:e2:
         f0:0e:10:d6:ec:8c:ed:d5:70:9b:3b:6e:cb:44:10:a4:c2:60:
         d3:57:3f:e5:2a:f7:6e:b6:34:a8:09:6c:97:c1:18:05:1b:52:
         55:56:ff:73:b0:b0:6c:a4:f7:6f:96:a2:b6:a2:a6:db:95:8a:
         df:05:af:4c:e1:35:55:5c:98:c5:d3:47:5b:82:2c:5f:e7:98:
         07:46:77:75:0e:d9:41:e6:fd:4d:8a:7a:b5:a6:9a:0b:96:af:
         93:b7:ba:27:99:fa:7a:61:e1:a7:36:e7:1e:4d:1d:36:92:a3:
         99:97:81:ac:8f:72:7e:a7:57:a8:b2:56:74:46:c6:02:f3:c3:
         51:57:e8:fe

[seriousme]

10.x fails on the websocket tests not related to this PR
(see https://github.com/mqttjs/MQTT.js/pull/1148/checks?check_run_id=1016492613#step:6:79481 )

[YoDaMa]

@seriousme are both commits necessary or can you squash them? Once that's resolved I'll approve and merge.

[seriousme]

I have squashed the commits into one.

Cheers,
Hans