Fix potential nil pointer dereference in RawRequestWithContext

[vigneshakaviki]

Fixes a potential nil pointer dereference where result.Error() is called without verifying result is non-nil first.

The code checks if result != nil for callbacks, but then calls result.Error() outside that block. This allows the Error() call when result is nil, causing a panic.

Fix: Move the result.Error() check inside the nil validation block.

Fixes #30209

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