misc: typo and grammar fixes

- Replace `Github` with `GitHub`.
- Replace `windows` with `Windows`
- Replace `advice` with `advise` where a verb is used.
- A few fixes on removing repeated words.
- Replace `a HTTP` with `an HTTP`

Closes #9802

packages/vms/curl_gnv_build_steps.txt

@@ -251,7 +251,7 @@ branding the PCSI kit based on who is making the kit.
       step of backing up the source files will probably hang or fail.
 
       You need to copy the source files to VMS mounted disks and create
-      logical names SRC_ROOT1 and VMS_ROOT1 to work around this to to
+      logical names SRC_ROOT1 and VMS_ROOT1 to work around this to
       reference local disks.  Make sure src_root1:[000000] and
       vms_root1:[000000] exist and can be written to.
 

packages/vms/curl_release_note_start.txt

@@ -58,12 +58,12 @@ For the HP SSL work around to work for GNV do the following:
  dcl @gnv\$gnu:[vms_bin]curl.com $*
  ^Z
 
-Similar work arounds will be needed for any program linked with GNV$LIBCURL
+Similar workarounds will be needed for any program linked with GNV$LIBCURL
 until the HP OpenSSL is upgraded to the current 1.4 version or later.
 
 If you are installing a "daily" build instead of a release build of Curl, some
 things have been changed so that it can be installed at the same time as
-a production build with out conflicts.
+a production build without conflicts.
 
    The CURL_DAILY_STARTUP.COM will be supplied instead of CURL_STARTUP.COM.
    This file is actually not used with the daily package and is provided as