Fix PreserveTitleAndBody bug

Set Title and Body to nil when setting is true

Test on my repository with both value, it works as expected.

.gitignore

@@ -1 +1,2 @@
 dist/
+.DS_Store

github/githubclient/client.go

@@ -378,12 +378,21 @@ func (c *client) UpdatePullRequest(ctx context.Context, gitcmd git.GitInterface,
 		Interface("PR", pr).Msg("UpdatePullRequest")
 
 	body := formatBody(commit, info.PullRequests)
-	_, err := c.api.UpdatePullRequest(ctx, genclient.UpdatePullRequestInput{
+	title := &commit.Subject
+
+	input := genclient.UpdatePullRequestInput{
 		PullRequestId: pr.ID,
 		BaseRefName:   &baseRefName,
-		Title:         &commit.Subject,
+		Title:         title,
 		Body:          &body,
-	})
+	}
+
+	if c.config.User.PreserveTitleAndBody {
+		input.Title = nil
+		input.Body = nil
+	}
+
+	_, err := c.api.UpdatePullRequest(ctx, input)
 
 	if err != nil {
 		log.Fatal().

readme.md

@@ -175,7 +175,7 @@ User specific configuration is saved to .spr.yml in the user home directory.
 | statusBitsHeader     | bool | true    | show status bits type headers                                     |
 | statusBitsEmojis     | bool | true    | show status bits using fancy emojis                               |
 | createDraftPRs       | bool | false   | new pull requests are created as draft                            |
-| PreserveTitleAndBody | bool | false   | updating pull requests will not overwrite the pr title and body   |
+| preserveTitleAndBody | bool | false   | updating pull requests will not overwrite the pr title and body   |
 
 Happy Coding!
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