Extend expiration of diagnose test-fixture certificate (hashicorp#19868)

- Regenerated with
    - openssl x509 -x509toreq -in xxx.crt -signkey xxx -out xxx.csr
    - openssl x509 -req -in xxx.csr -signkey xxx.pem -days 18250 -out xxx.crt

vault/diagnose/test-fixtures/ecdsa.crt

@@ -1,14 +1,15 @@
 -----BEGIN CERTIFICATE-----
-MIICPDCCAcMCCQCbpXTR6v+lUDAKBggqhkjOPQQDAjCBhzELMAkGA1UEBhMCVVMx
-CzAJBgNVBAgMAkNBMQswCQYDVQQHDAJQSDESMBAGA1UECgwJSGFzaGljb3JwMQ4w
-DAYDVQQLDAVWYXVsdDEYMBYGA1UEAwwPZWNkc2EudmF1bHQuY29tMSAwHgYJKoZI
-hvcNAQkBFhFyb3lAaGFzaGljb3JwLmNvbTAeFw0yMTA0MDcxNDUxMTBaFw0yMzA0
-MDcxNDUxMTBaMIGHMQswCQYDVQQGEwJVUzELMAkGA1UECAwCQ0ExCzAJBgNVBAcM
-AlBIMRIwEAYDVQQKDAlIYXNoaWNvcnAxDjAMBgNVBAsMBVZhdWx0MRgwFgYDVQQD
-DA9lY2RzYS52YXVsdC5jb20xIDAeBgkqhkiG9w0BCQEWEXJveUBoYXNoaWNvcnAu
-Y29tMHYwEAYHKoZIzj0CAQYFK4EEACIDYgAEQHr9wo78LVd2y/pU/EZkQ+JDVDPV
-2rmRIYMaDSrBpKypJsiO7p+vc7miCZO/lXneAZiFxwX5FDGlBIUSQnGmkHlpKY0c
-hP6ogNKknoCjBFgFG0Rq3wYAgHg/6dJ6SNlGMAoGCCqGSM49BAMCA2cAMGQCMB0W
-UpmSWnLxmLxDmYVbmut+xJnJVSc+nGn9IiV3HhW5q20kj2kXnqD9jnRcV97kewIw
-TnF+AASW0Pyn4h+cWNNv6am03eM6jHZLNQY8V1R8WlHF7Hk8T6YDpL/gvsaipp/W
+MIICSTCCAdACFEjzHOj+v+Do1IeND8+HQQpWDtcNMAoGCCqGSM49BAMCMIGHMQsw
+CQYDVQQGEwJVUzELMAkGA1UECAwCQ0ExCzAJBgNVBAcMAlBIMRIwEAYDVQQKDAlI
+YXNoaWNvcnAxDjAMBgNVBAsMBVZhdWx0MRgwFgYDVQQDDA9lY2RzYS52YXVsdC5j
+b20xIDAeBgkqhkiG9w0BCQEWEXJveUBoYXNoaWNvcnAuY29tMCAXDTIzMDMzMDE4
+MDE0MVoYDzIwNzMwMzE3MTgwMTQxWjCBhzELMAkGA1UEBhMCVVMxCzAJBgNVBAgM
+AkNBMQswCQYDVQQHDAJQSDESMBAGA1UECgwJSGFzaGljb3JwMQ4wDAYDVQQLDAVW
+YXVsdDEYMBYGA1UEAwwPZWNkc2EudmF1bHQuY29tMSAwHgYJKoZIhvcNAQkBFhFy
+b3lAaGFzaGljb3JwLmNvbTB2MBAGByqGSM49AgEGBSuBBAAiA2IABEB6/cKO/C1X
+dsv6VPxGZEPiQ1Qz1dq5kSGDGg0qwaSsqSbIju6fr3O5ogmTv5V53gGYhccF+RQx
+pQSFEkJxppB5aSmNHIT+qIDSpJ6AowRYBRtEat8GAIB4P+nSekjZRjAKBggqhkjO
+PQQDAgNnADBkAjBpUEBCoOFTDAKvnmNORxnQidtV0niSbS3Kn3BA2Kl/pZ9yiXZy
+o+PBIcQfR3gXBvICMC8JVQzPMyoPPaAMqZmFnFn2God2CekEjRJRHdZFptey4ozX
+q9s+Rj3XNfdr8KUmPQ==
 -----END CERTIFICATE-----