Printer Settings: Fix browse button alignment

• Adjusted file input size to accommodate long localized text

Screenshots:

Before:
• add manufacturer/model dialog: http://shortn/_vclFeWHF7F
• edit dialog: http://shortn/_7jVZAAwuxU

After:
• add manufacturer/model dialog: http://shortn/_r1l2s42oOu
• edit dialog: http://shortn/_Nv8DPj55sE

BUG=1100158
TEST=manual inspection

Change-Id: I1d65cc68f5730c1cc94ac22a54834e9d7ffaae65
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2357415Reviewed-by: Jimmy Gong <jimmyxgong@chromium.org>
Reviewed-by: Zentaro Kavanagh <zentaro@chromium.org>
Commit-Queue: Michael Checo <michaelcheco@google.com>
Cr-Commit-Position: refs/heads/master@{#801040}

chrome/browser/resources/settings/chromeos/os_printing_page/cups_printer_shared_css.html

@@ -37,8 +37,8 @@
       }
 
       [slot='dialog-body'] .settings-box .browse-file-input {
+        flex: 1;
         width: auto;
-        --cr-input-width: 383px;
       }
 
       [slot='dialog-body'] .settings-box .browse-button {