Add more fatal error diagnostics

[mlwilkerson]

When fatal errors are notified to the WordPress admin (and only admin), the following additional diagnostic information like this:

php version: 7.3.15
WordPress version: 5.3.2
multisite: false
is_network_admin: false
curl loaded: true
curl version_number: 475136
curl features: 4179869
curl ssl_version_number: 0
curl version: 7.64.0
curl host: x86_64-pc-linux-gnu
curl ssl_version: OpenSSL/1.1.1d
openssl loaded: true
openssl cipher methods: aes-128-cbc,aes-128-cbc-hmac-sha1,aes-128-cbc-hmac-sha256,aes-128-ccm,aes-128-cfb,aes-128-cfb1,aes-128-cfb8,aes-128-ctr,aes-128-ecb,aes-128-gcm,aes-128-ocb,aes-128-ofb,aes-128-xts,aes-192-cbc,aes-192-ccm,aes-192-cfb,aes-192-cfb1,aes-192-cfb8,aes-192-ctr,aes-192-ecb,aes-192-gcm,aes-192-ocb,aes-192-ofb,aes-256-cbc,aes-256-cbc-hmac-sha1,aes-256-cbc-hmac-sha256,aes-256-ccm,aes-256-cfb,aes-256-cfb1,aes-256-cfb8,aes-256-ctr,aes-256-ecb,aes-256-gcm,aes-256-ocb,aes-256-ofb,aes-256-xts,aria-128-cbc,aria-128-ccm,aria-128-cfb,aria-128-cfb1,aria-128-cfb8,aria-128-ctr,aria-128-ecb,aria-128-gcm,aria-128-ofb,aria-192-cbc,aria-192-ccm,aria-192-cfb,aria-192-cfb1,aria-192-cfb8,aria-192-ctr,aria-192-ecb,aria-192-gcm,aria-192-ofb,aria-256-cbc,aria-256-ccm,aria-256-cfb,aria-256-cfb1,aria-256-cfb8,aria-256-ctr,aria-256-ecb,aria-256-gcm,aria-256-ofb,bf-cbc,bf-cfb,bf-ecb,bf-ofb,camellia-128-cbc,camellia-128-cfb,camellia-128-cfb1,camellia-128-cfb8,camellia-128-ctr,camellia-128-ecb,camellia-128-ofb,camellia-192-cbc,camellia-192-cfb,camellia-192-cfb1,camellia-192-cfb8,camellia-192-ctr,camellia-192-ecb,camellia-192-ofb,camellia-256-cbc,camellia-256-cfb,camellia-256-cfb1,camellia-256-cfb8,camellia-256-ctr,camellia-256-ecb,camellia-256-ofb,cast5-cbc,cast5-cfb,cast5-ecb,cast5-ofb,chacha20,chacha20-poly1305,des-cbc,des-cfb,des-cfb1,des-cfb8,des-ecb,des-ede,des-ede-cbc,des-ede-cfb,des-ede-ofb,des-ede3,des-ede3-cbc,des-ede3-cfb,des-ede3-cfb1,des-ede3-cfb8,des-ede3-ofb,des-ofb,desx-cbc,id-aes128-CCM,id-aes128-GCM,id-aes128-wrap,id-aes128-wrap-pad,id-aes192-CCM,id-aes192-GCM,id-aes192-wrap,id-aes192-wrap-pad,id-aes256-CCM,id-aes256-GCM,id-aes256-wrap,id-aes256-wrap-pad,id-smime-alg-CMS3DESwrap,rc2-40-cbc,rc2-64-cbc,rc2-cbc,rc2-cfb,rc2-ecb,rc2-ofb,rc4,rc4-40,rc4-hmac-md5,seed-cbc,seed-cfb,seed-ecb,seed-ofb,sm4-cbc,sm4-cfb,sm4-ctr,sm4-ecb,sm4-ofb