doc: fix grammar errors in submodule description

6cc6d1b (Documentation: update add --force option + ignore=all
config, 2026-02-06) added text describing both the ignore=none and
ignore=all behaviors.  The former had minor formatting and grammatical
errors, while the latter was a bit garbled.  I have tried to tweak the
wording on the latter to make it read as I think was intended, and fixed
the minor grammatical issues with both as well.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: newren

Documentation/config/submodule.adoc

@@ -40,7 +40,7 @@ submodule.<name>.ignore::
 	takes only differences between the HEAD of the submodule and the commit
 	recorded in the superproject into account. "untracked" will additionally
 	let submodules with modified tracked files in their work tree show up.
-	When set to "none"(default) It also show submodules as changed if they have
+	When set to "none" (default) it also shows submodules as changed if they have
 	untracked files in their work tree.
 	This setting overrides any setting made in .gitmodules for this submodule,
 	both settings can be overridden on the command line by using the

Documentation/gitmodules.adoc

@@ -70,10 +70,10 @@ submodule.<name>.ignore::
 --
 	all;; The submodule will never be considered modified (but will
 	    nonetheless show up in the output of status and commit when it has
-	    been staged). Add `(new commits)` can be overruled using the
-	    `git add --force <submodule.path>`.
-		The setting affects `status`, `update-index`, `diff` and `log`(due
-		to underlaying `diff`).
+	    been staged).  Adding a submodule with `(new commits)` can be
+	    overridden using `git add --force <submodule.path>`.
+	    This setting affects `status`, `update-index`, `diff` and `log`
+	    (due to underlying `diff`).
 
 	dirty;; All changes to the submodule's work tree will be ignored, only
 	    committed differences between the `HEAD` of the submodule and its