Turn on substitutions and lint only added lines in style workflow (#4025)

Signed-off-by: Fanit Kolchina <kolchfa@amazon.com>

.github/workflows/vale.yml

@@ -18,5 +18,5 @@ jobs:
         with:
           fail_on_error: false
           reporter: github-pr-check
-          filter_mode: file
+          filter_mode: added
           vale_flags: "--no-exit"

.vale.ini

@@ -58,7 +58,7 @@ OpenSearch.SpacingSlash = NO
 OpenSearch.SpacingWords = NO
 OpenSearch.Spelling = YES
 OpenSearch.StackedHeadings = NO
-OpenSearch.SubstitutionsError = NO
+OpenSearch.SubstitutionsError = YES
 OpenSearch.SubstitutionsSuggestion = NO
 OpenSearch.TableHeadings = NO
 OpenSearch.TimeoutNoun = NO