Remove a valgrind suppression for Brotli decoder

This was fixed in https://codereview.chromium.org/766523003

BUG=411235

Review URL: https://codereview.chromium.org/804903003

Cr-Commit-Position: refs/heads/master@{#308492}

tools/valgrind/memcheck/suppressions.txt

@@ -3283,15 +3283,6 @@
    fun:_ZN5blink20InlineTextBoxPainter5paintERNS_9PaintInfoERKNS_11LayoutPointE
    fun:_ZN5blink13InlineTextBox5paintERNS_9PaintInfoERKNS_11LayoutPointENS_10LayoutUnitES6_
 }
-{
-   bug_411235
-   Memcheck:Overlap
-   fun:memcpy@@GLIBC_2.14
-   fun:IncrementalCopyFastPath
-   fun:BrotliDecompress
-   fun:BrotliDecompressBuffer
-   fun:_ZN12_GLOBAL__N_115Woff2UncompressEPhmPKhmj
-}
 {
    bug_415092
    Memcheck:Leak