swaplabel: add page (#10462)

* swaplabel: add page

---------

Co-authored-by: Lena <126529524+acuteenvy@users.noreply.github.com>

pages/linux/swaplabel.md

@@ -0,0 +1,17 @@
+# swaplabel
+
+> Print or change the label or UUID of a swap area.
+> Note: `path/to/file` can either point to a regular file or a swap partition.
+> More information: <https://manned.org/swaplabel>.
+
+- Display the current label and UUID of a swap area:
+
+`swaplabel {{path/to/file}}`
+
+- Set the label of a swap area:
+
+`swaplabel --label {{new_label}} {{path/to/file}}`
+
+- Set the UUID of a swap area (you can generate a UUID using `uuidgen`):
+
+`swaplabel --uuid {{new_uuid}} {{path/to/file}}`