URL entry fields should automatically remove leading/trailing spaces or newlines

[Sinus Pi]

What steps will reproduce the problem?

1. Paste an URL with leading or trailing spaces or newlines into the GetCapabilities url field (2)
2. Hit (3)
3. See an error

What is the expected result?

The URL should be sanitized to remove whitespace

What happens instead?

JOSM tries to use the URL as-is, with whitespace

Please provide any additional information below. Attach a screenshot if possible.

URL:https://josm.openstreetmap.de/svn/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2020-12-28 22:03:23 +0100 (Mon, 28 Dec 2020)
Build-Date:2020-12-30 02:30:55
Revision:17428
Relative:URL: ^/trunk

Identification: JOSM/1.5 (17428 pl) Windows 10 64-Bit
OS Build number: Windows 10 Home 1909 (18363)
Memory Usage: 813 MB / 1820 MB (416 MB allocated, but free)
Java version: 1.8.0_271-b09, Oracle Corporation, Java HotSpot(TM) 64-Bit Server VM
Look and Feel: com.sun.java.swing.plaf.windows.WindowsLookAndFeel
Screen: \Display0 1920×1080 (scaling 1,00×1,00) \Display1 1680×1050 (scaling 1,00×1,00)
Maximum Screen Size: 1920×1080
Best cursor sizes: 16×16→32×32, 32×32→32×32
VM arguments: [-Djava.security.manager, -Djava.security.policy=file:<java.home>\lib\security\javaws.policy, -DtrustProxy=true, -Djnlpx.home=<java.home>\bin, -Djnlpx.origFilenameArg=%UserProfile%\Downloads\josm.jnlp, -Djnlpx.remove=false, -Djava.util.Arrays.useLegacyMergeSort=true, -Djnlpx.heapsize=NULL,2048m, -Djnlpx.splashport=19684, -Djnlpx.jvm=<java.home>\bin\javaw.exe]
Dataset consistency test: No problems found

Plugins:
+ PicLayer (2a9aa7a)
+ apache-commons (35524)
+ areaselector (368)
+ austriaaddresshelper (1597341117)
+ buildings_tools (35669)
+ ejml (35458)
+ geotools (35458)
+ jaxb (35543)
+ jts (35458)
+ log4j (35458)
+ opendata (35640)
+ utilsplugin2 (35691)

Map paint styles:
+ https://josm.openstreetmap.de/josmfile?page=Styles/HiDPISupport&zip=1
+ https://josm.openstreetmap.de/josmfile?page=Styles/NewHighwayColors&zip=1
+ C:\DOKUMENTY\elemstyles.mapcss
- https://josm.openstreetmap.de/josmfile?page=Styles/Modified&zip=1

Last errors/warnings:
- 00236,375 E: Could not parse WMS layer list. Incoming data:
- 02145,609 E: java.nio.file.InvalidPathException: Illegal char <:> at index 5: https:\integracja.gugik.gov.pl\cgi-bin\KrajowaIntegracjaEwidencjiGruntow?SERVICE=WMS&REQUEST=GetCapabilities&language=pol

[Don-vip]

In 17543/josm:

fix #20535 - strip leading/trailing whitespace from URLs entered in "Add WMS/WMTS" dialogs