Update default severity in record issue and update isFailure check

Author: suzannaratcliff

Sources/Testing/ABI/EntryPoints/EntryPoint.swift

@@ -42,7 +42,7 @@ func entryPoint(passing args: __CommandLineArguments_v0?, eventHandler: Event.Ha
 
     // Set up the event handler.
     configuration.eventHandler = { [oldEventHandler = configuration.eventHandler] event, context in
-      if case let .issueRecorded(issue) = event.kind, !issue.isKnown, issue.severity >= .error {
+      if case let .issueRecorded(issue) = event.kind, issue.isFailure {
         exitCode.withLock { exitCode in
           exitCode = EXIT_FAILURE
         }

Sources/Testing/Issues/Issue+Recording.swift

@@ -73,7 +73,7 @@ extension Issue {
   /// or ``require(_:_:sourceLocation:)-5l63q`` macros.)
   @discardableResult public static func record(
     _ comment: Comment? = nil,
-    severity: Severity,
+    severity: Severity = .error,
     sourceLocation: SourceLocation = #_sourceLocation
   ) -> Self {
     let sourceContext = SourceContext(backtrace: .current(), sourceLocation: sourceLocation)
@@ -104,7 +104,7 @@ extension Issue {
   @discardableResult public static func record(
     _ error: any Error,
     _ comment: Comment? = nil,
-    severity: Severity,
+    severity: Severity = .error,
     sourceLocation: SourceLocation = #_sourceLocation
   ) -> Self {
     let backtrace = Backtrace(forFirstThrowOf: error) ?? Backtrace.current()

Sources/Testing/Issues/Issue.swift

@@ -104,7 +104,7 @@ public struct Issue: Sendable {
 
   /// If the issues is a failing issue.
   public var isFailure: Bool {
-    severity == .error
+    return !self.isKnown && self.severity >= .error
   }
 
   /// Any comments provided by the developer and associated with this issue.