Basics: fix DiagnosticsHanderWrapper typo (#5877)

Applied renaming to `DiagnosticsHandlerWrapper` within `Basics/Observability.swift`.

Author: MaxDesiatov

Sources/Basics/Observability.swift

@@ -66,7 +66,7 @@ public final class ObservabilityScope: DiagnosticsEmitterProtocol, CustomStringC
     private let parent: ObservabilityScope?
     private let metadata: ObservabilityMetadata?
 
-    private var diagnosticsHandler: DiagnosticsHanderWrapper
+    private var diagnosticsHandler: DiagnosticsHandlerWrapper
 
     fileprivate init(
         description: String,
@@ -77,7 +77,7 @@ public final class ObservabilityScope: DiagnosticsEmitterProtocol, CustomStringC
         self.description = description
         self.parent = parent
         self.metadata = metadata
-        self.diagnosticsHandler = DiagnosticsHanderWrapper(diagnosticsHandler)
+        self.diagnosticsHandler = DiagnosticsHandlerWrapper(diagnosticsHandler)
     }
 
     public func makeChildScope(description: String, metadata: ObservabilityMetadata? = .none) -> Self {
@@ -127,7 +127,7 @@ public final class ObservabilityScope: DiagnosticsEmitterProtocol, CustomStringC
         self.diagnosticsHandler.handleDiagnostic(scope: self, diagnostic: diagnostic)
     }
 
-    private struct DiagnosticsHanderWrapper: DiagnosticsHandler {
+    private struct DiagnosticsHandlerWrapper: DiagnosticsHandler {
         private let underlying: DiagnosticsHandler
         private var _errorsReported = ThreadSafeBox<Bool>(false)
 
@@ -375,7 +375,7 @@ public struct Diagnostic: CustomStringConvertible {
 /// Note that specific baggage and context types MAY (and usually do), offer also a way to set baggage values,
 /// however in the most general case it is not required, as some frameworks may only be able to offer reading.
 
-// FIXME: we currently requires that Value conforms to CustomStringConvertible which sucks
+// FIXME: we currently require that Value conforms to CustomStringConvertible which sucks
 // ideally Value would conform to Equatable but that has generic requirement
 // luckily, this is about to change so we can clean this up soon
 public struct ObservabilityMetadata: CustomDebugStringConvertible {