do not trucate error message from template evaluation (#1038)

Author: ericsciple

src/Runner.Worker/ActionManifestManager.cs

@@ -311,7 +311,7 @@ private TemplateContext CreateTemplateContext(
             var result = new TemplateContext
             {
                 CancellationToken = CancellationToken.None,
-                Errors = new TemplateValidationErrors(10, 500),
+                Errors = new TemplateValidationErrors(10, int.MaxValue), // Don't truncate error messages otherwise we might not scrub secrets correctly
                 Memory = new TemplateMemory(
                     maxDepth: 100,
                     maxEvents: 1000000,

src/Runner.Worker/ExecutionContext.cs

@@ -979,7 +979,10 @@ public static PipelineTemplateEvaluator ToPipelineTemplateEvaluator(this IExecut
                 traceWriter = context.ToTemplateTraceWriter();
             }
             var schema = PipelineTemplateSchemaFactory.GetSchema();
-            return new PipelineTemplateEvaluator(traceWriter, schema, context.Global.FileTable);
+            return new PipelineTemplateEvaluator(traceWriter, schema, context.Global.FileTable)
+            {
+                MaxErrorMessageLength = int.MaxValue, // Don't truncate error messages otherwise we might not scrub secrets correctly
+            };
         }
 
         public static ObjectTemplating.ITraceWriter ToTemplateTraceWriter(this IExecutionContext context)

src/Sdk/DTPipelines/Pipelines/ObjectTemplating/PipelineTemplateEvaluator.cs

@@ -40,7 +40,7 @@ public PipelineTemplateEvaluator(
         /// <summary>
         /// Gets the maximum error message length before the message will be truncated.
         /// </summary>
-        public Int32 MaxErrorMessageLength => 500;
+        public Int32 MaxErrorMessageLength { get; set; } = 500;
 
         /// <summary>
         /// Gets the maximum number of errors that can be recorded when parsing a pipeline.