Align on writing "SHA" in "allowTipSHA1InWant"

Even if git-config key names are case-insensitive, align on writing
"allowTipSHA1InWant" with upper-cased "SHA" as that is how Git upstream
[1] and Gerrit code [2] do it.

[1] https://git-scm.com/docs/git-config#git-config-uploadpackallowTipSHA1InWant
[2] https://gerrit.googlesource.com/plugins/download-commands/+/refs/heads/master/src/main/java/com/googlesource/gerrit/plugins/download/command/GitDownloadCommand.java#42

Change-Id: Ie28ceec4703e22d696a3601a0e61ad52ca121b29
diff --git a/src/main/resources/Documentation/config.md b/src/main/resources/Documentation/config.md
index 3e76bdb..bcd27a9 100644
--- a/src/main/resources/Documentation/config.md
+++ b/src/main/resources/Documentation/config.md
@@ -74,7 +74,7 @@
 	advertisement (`uploadpack.hideRefs`). This option can be used to
 	hide the change refs from the client. As consequence fetching
 	changes by change ref does not work anymore. However by setting
-	`uploadpack.allowTipSha1InWant` to `true` fetching changes by
+	`uploadpack.allowTipSHA1InWant` to `true` fetching changes by
 	commit ID is possible. If `download.checkForHiddenChangeRefs` is
 	set to `true` the git download commands use the commit ID instead
 	of the change ref when a project is configured like this.
@@ -84,6 +84,6 @@
 		[uploadpack]
 		  hideRefs = refs/changes/
 		  hideRefs = refs/cache-automerge/
-		  allowTipSha1InWant = true
+		  allowTipSHA1InWant = true
 
 	By default `false`.