[clang] [clang-format] Add KeepEmptyLines.AtEndOfBlock option (PR #224223)

[Arkadiusz Bokowy via cfe-commits]

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@@ -397,6 +398,7 @@ TEST_F(FormatTest, RemovesEmptyLines) {
   Style.BraceWrapping.AfterClass = true;
   Style.BraceWrapping.AfterFunction = true;
   Style.KeepEmptyLines.AtStartOfBlock = false;
+  Style.KeepEmptyLines.AtEndOfBlock = false;
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arkq wrote:

> The presence suggests the executed test depends on that value. If it is relevant, that the option is set to false then ASSERT_EQ on that.

OK I'll remove that one. However, the `AtStartOfBlock` is also not tested here :D The test passes regardless of the value (setting it to `true` does not fail the test).

https://github.com/llvm/llvm-project/pull/224223