[FIX] web_editor: changing header style keep its text alignment

Before this commit:

changing header style, changes the alignment of the selection

After this commit:

Now after applying header on selection it doesnot changes its alignment.

Task-2641462

closes odoo/odoo#99358

X-original-commit: da8d2669b03e1016dc05f031a2a7ac840541962e
Signed-off-by: David Monjoie (dmo) <dmo@odoo.com>

addons/web_editor/static/src/js/editor/odoo-editor/src/commands/commands.js

@@ -586,7 +586,12 @@ export const editorCommands = {
             ) {
                 setSelection(block, 0, block, nodeSize(block));
                 editor.historyPauseSteps();
+                // Keep the alignment and remove rest of the applied styles.
+                const textAlign = block.style.textAlign;
                 editor.execCommand('removeFormat');
+                if (textAlign) {
+                    block.style.textAlign = textAlign;
+                }
                 editor.historyUnpauseSteps();
                 const inLI = block.closest('li');
                 if (inLI && tagName === "P") {