Fix dumb memory error when reading buffers

Not sure how this got in, and I'm even less sure why this has not caused
any issues before this. In the particular case that was causing a crash,
the host was sending 138 sample sized buffers. This error likely only
became visible because the lack of memory alignment caused writes to
parts of the vector objects themselves.

src/plugin/plugin-bridge.cpp

@@ -512,7 +512,7 @@ void PluginBridge::process_replacing(AEffect* /*plugin*/,
     std::vector<std::vector<float>> input_buffers(
         plugin.numInputs, std::vector<float>(sample_frames));
     for (int channel = 0; channel < plugin.numInputs; channel++) {
-        std::copy(inputs[channel], inputs[channel] + sample_frames + 1,
+        std::copy(inputs[channel], inputs[channel] + sample_frames,
                   input_buffers[channel].begin());
     }