Fix error displayed when insights files can't be found and fix server-report insights in dev build (#18635)

* Fix error

* fix queries

extensions/server-report/sql/memorybydb.sql

@@ -0,0 +1,30 @@
+-- source:https://www.mssqltips.com/sqlservertip/2393/determine-sql-server-memory-use-by-database-and-object/
+-- Use for a demo/sample purpose only. This query is not built-in to any product.
+
+DECLARE @total_buffer INT;
+
+SELECT @total_buffer = cntr_value
+FROM sys.dm_os_performance_counters 
+WHERE RTRIM([object_name]) LIKE '%Buffer Manager'
+AND counter_name = 'Database Pages';
+
+;WITH src AS
+(
+SELECT 
+database_id, db_buffer_pages = COUNT_BIG(*)
+FROM sys.dm_os_buffer_descriptors
+--WHERE database_id BETWEEN 5 AND 32766
+GROUP BY database_id
+)
+SELECT TOP 10 
+[db_name] = CASE [database_id] WHEN 32767 
+THEN 'Resource DB' 
+ELSE DB_NAME([database_id]) END,
+--db_buffer_pages,
+--db_buffer_MB = db_buffer_pages / 128,
+db_buffer_percent = CONVERT(DECIMAL(6,3), 
+db_buffer_pages * 100.0 / @total_buffer)
+FROM src
+--ORDER BY db_buffer_MB DESC; 
+order by db_buffer_percent DESC;
+