spellcheck: adapt to backslashed minuses

As the curl.1 has more backslashed minus, the cleanup sed lines xneed to
adapt.

Adjusted some docs slighly.

Follow-up to 439ff2052e

Closes #11663

.github/scripts/spellcheck.words

@@ -853,6 +853,8 @@ Viktor
 VM
 VMS
 VMware
+VRF
+VRFY
 VSE
 vsprintf
 vt

.github/workflows/spellcheck.yml

@@ -54,7 +54,7 @@ jobs:
     - name: trim the curl.1 markdown file
       run: |
         perl -pi -e 's/^    .*//' docs/curl.md
-        perl -pi -e 's/--[a-z0-9-]*//ig' docs/curl.md
+        perl -pi -e 's/\-\-[\a-z0-9-]*//ig' docs/curl.md
         perl -pi -e 's!https://[a-z0-9%/.-]*!!ig' docs/curl.md
 
     - name: setup the custom wordlist

docs/cmdline-opts/login-options.d

@@ -13,9 +13,10 @@ Multi: single
 Specify the login options to use during server authentication.
 
 You can use login options to specify protocol specific options that may be
-used during authentication. At present only IMAP, POP3 and SMTP support
-login options. For more information about login options please see RFC
-2384, RFC 5092 and the IETF draft **draft-earhart-url-smtp-00.txt**.
+used during authentication. At present only IMAP, POP3 and SMTP support login
+options. For more information about login options please see RFC 2384,
+RFC 5092 and the IETF draft
+https://datatracker.ietf.org/doc/html/draft-earhart-url-smtp-00.
 
 Since 8.2.0, IMAP supports the login option "AUTH=+LOGIN". With this option,
 curl uses the plain (not SASL) LOGIN IMAP command even if the server advertises

docs/cmdline-opts/mail-rcpt.d

@@ -13,7 +13,7 @@ Multi: append
 Specify a single email address, user name or mailing list name. Repeat this
 option several times to send to multiple recipients.
 
-When performing an address verification (*VRFY* command), the recipient should be
+When performing an address verification (**VRFY** command), the recipient should be
 specified as the user name or user name and domain (as per Section 3.5 of
 RFC 5321). (Added in 7.34.0)
 

docs/cmdline-opts/output.d

@@ -44,6 +44,6 @@ To suppress response bodies, you can redirect output to /dev/null:
 
  curl example.com -o /dev/null
 
-Or for Windows use **nul**:
+Or for Windows:
 
  curl example.com -o nul

docs/cmdline-opts/request.d

@@ -46,6 +46,6 @@ Specifies a custom POP3 command to use instead of *LIST* or *RETR*.
 Specifies a custom IMAP command to use instead of *LIST*. (Added in 7.30.0)
 .TP
 **SMTP**
-Specifies a custom SMTP command to use instead of *HELP* or *VRFY*. (Added in 7.34.0)
+Specifies a custom SMTP command to use instead of *HELP* or **VRFY**. (Added in 7.34.0)
 .RE
 .IP