Delete .clang-format

This file isn't accurate, and clang-format can't describe our code
style.

References: https://github.com/swaywm/sway/pull/6249#issuecomment-986214042

.clang-format

@@ -1,18 +0,0 @@
-BasedOnStyle: LLVM
-IndentWidth: 4
-TabWidth: 4
-UseTab: Always
-BreakBeforeBraces: Attach
-AllowShortIfStatementsOnASingleLine: false
-IndentCaseLabels: false
-SortIncludes: false
-ColumnLimit: 80
-AlignAfterOpenBracket: DontAlign
-BinPackParameters: true
-BinPackArguments: true
-ContinuationIndentWidth: 8
-AllowAllParametersOfDeclarationOnNextLine: false
-AllowShortLoopsOnASingleLine: true
-ReflowComments: false
-AllowAllArgumentsOnNextLine: false
-AlignOperands: DontAlign