Tests: Message log level tests must fail on unwanted output

The previous regular expressions were allowing output from
lower log levels. The tests still pass after these changes but will
now catch regressions (previously they would not have).

Tests/RunCMake/message/message-log-level-debug-stdout.txt

@@ -1,3 +1,3 @@
 -- STATUS message
 -- VERBOSE message
--- DEBUG message
+-- DEBUG message$

Tests/RunCMake/message/message-log-level-default-stdout.txt

@@ -1 +1 @@
--- STATUS message
+-- STATUS message$

Tests/RunCMake/message/message-log-level-status-stdout.txt

@@ -1 +1 @@
--- STATUS message
+-- STATUS message$

Tests/RunCMake/message/message-log-level-trace-stdout.txt

@@ -1,4 +1,4 @@
 -- STATUS message
 -- VERBOSE message
 -- DEBUG message
--- TRACE message
+-- TRACE message$

Tests/RunCMake/message/message-log-level-verbose-stdout.txt

@@ -1,2 +1,2 @@
 -- STATUS message
--- VERBOSE message
+-- VERBOSE message$

Tests/RunCMake/message/message-loglevel-debug-stdout.txt

@@ -1,3 +1,3 @@
 -- STATUS message
 -- VERBOSE message
--- DEBUG message
+-- DEBUG message$

Tests/RunCMake/message/message-loglevel-default-stdout.txt

@@ -1 +1 @@
--- STATUS message
+-- STATUS message$

Tests/RunCMake/message/message-loglevel-status-stdout.txt

@@ -1 +1 @@
--- STATUS message
+-- STATUS message$

Tests/RunCMake/message/message-loglevel-trace-stdout.txt

@@ -1,4 +1,4 @@
 -- STATUS message
 -- VERBOSE message
 -- DEBUG message
--- TRACE message
+-- TRACE message$

Tests/RunCMake/message/message-loglevel-verbose-stdout.txt

@@ -1,2 +1,2 @@
 -- STATUS message
--- VERBOSE message
+-- VERBOSE message$