[lit] Remove unnecessary testcases from lit-quoting.txt that fail on …

…macOS

These were added in 3793540,
but they fail on macOS (and on Windows with MSYS based tools, before
relanding D98859). Remove the tests that exercise "not not echo", as
the primary thing to test is the plain echo patterns above.

llvm/test/Other/lit-quoting.txt

@@ -4,12 +4,6 @@ RUN: echo 'a[b\c' | FileCheck %s --check-prefix=CHECK2
 RUN: echo "a[b\\c" | FileCheck %s --check-prefix=CHECK2
 RUN: echo 'a\b\\c\\\\d' | FileCheck %s --check-prefix=CHECK3
 RUN: echo "a\\b\\\\c\\\\\\\\d" | FileCheck %s --check-prefix=CHECK3
-RUN: not not echo "\"" | FileCheck %s --check-prefix=CHECK1
-RUN: not not echo '"' | FileCheck %s --check-prefix=CHECK1
-RUN: not not echo 'a[b\c' | FileCheck %s --check-prefix=CHECK2
-RUN: not not echo "a[b\\c" | FileCheck %s --check-prefix=CHECK2
-RUN: not not echo 'a\b\\c\\\\d' | FileCheck %s --check-prefix=CHECK3
-RUN: not not echo "a\\b\\\\c\\\\\\\\d" | FileCheck %s --check-prefix=CHECK3
 CHECK1: {{^"$}}
 CHECK2: {{^a\[b\\c$}}
 CHECK3: {{^a\\b\\\\c\\\\\\\\d$}}