Link validation job fails for invalid links with special characters

Description

Steps to reproduce

1. Link to //#_ftn1.
2. Run Link Validation job.

Expected:
Link is ignored

Actual:
Job stops with exception

WORKAROUND: Remove invalid URL from tblSoftLink

2018-09-27 00:00:17,640 [1429] ERROR EPiServer.DataAbstraction.ScheduledJob: Job EPiServer.LinkAnalyzer.LinkValidationJob failed for the job 'Koblingsvalidering' with jobId ='6bce1827-f306-476a-b766-2b35838f6ea0'
System.UriFormatException: Invalid URI: The hostname could not be parsed.
at System.Uri.CreateThis(String uri, Boolean dontEscape, UriKind uriKind)
at System.Uri..ctor(Uri baseUri, Uri relativeUri)
at EPiServer.Web.UriUtil.IsStringWellFormedUri(String uriString)
at EPiServer.LinkAnalyzer.Internal.LinkValidationRunner.CheckAndUpdateStatus(SoftLink link)
at EPiServer.LinkAnalyzer.Internal.LinkValidationRunner.CheckAndUpdateStatus(IEnumerable`1 softLinks)
at EPiServer.LinkAnalyzer.Internal.LinkValidationRunner.ValidateLinks()
at EPiServer.Scheduler.Internal.DefaultScheduledJobExecutor.<Execute>d__31.MoveNext()
System.UriFormatException: Invalid URI: The hostname could not be parsed.
at System.Uri.CreateThis(String uri, Boolean dontEscape, UriKind uriKind)
at System.Uri..ctor(Uri baseUri, Uri relativeUri)
at EPiServer.Web.UriUtil.IsStringWellFormedUri(String uriString)
at EPiServer.LinkAnalyzer.Internal.LinkValidationRunner.CheckAndUpdateStatus(SoftLink link)
at EPiServer.LinkAnalyzer.Internal.LinkValidationRunner.CheckAndUpdateStatus(IEnumerable`1 softLinks)
at EPiServer.LinkAnalyzer.Internal.LinkValidationRunner.ValidateLinks()
at EPiServer.Scheduler.Internal.DefaultScheduledJobExecutor.<Execute>d__31.MoveNext()