Atom/qingtao/image builder fixes (#6432)

* LYN-8837 o3de Material Editor - Texture Settings Editor - Hangs when converting texture (#6359)

Fixed a editor hanging issue when preview texture with astc format (starts multiple job threads inside a job thread)
Fixed an issue of changing texture setting didn't trigger image re-process.
Fixed an issue with image asset which has texture setting may have dependency with wrong preset
Added a EIF_HDR for source image in hdr format.
Fixed astc compression issue which may wrongly compress image to HDR astc format

Signed-off-by: Qing Tao <55564570+VickyAtAZ@users.noreply.github.com>
(cherry picked from commit d9f0a3012d)

* ATOM-16958 [Image Builder] Alpha data would be removed for source image with alpha content (#6412)

Fixed a regression issue with image builder which it can choose proper preset for images with alpha content.

Signed-off-by: Qing Tao <55564570+VickyAtAZ@users.noreply.github.com>
(cherry picked from commit b640f6d691)

Gems/Atom/Asset/ImageProcessingAtom/Code/Source/Processing/ImageConvert.cpp

@@ -193,7 +193,7 @@ namespace ImageProcessingAtom
                     }
 
                     m_image->Get()->Swizzle(swizzle.c_str());
-                    if (!m_input->m_presetSetting.m_discardAlpha)
+                    if (m_input->m_presetSetting.m_discardAlpha)
                     {
                         m_alphaContent = EAlphaContent::eAlphaContent_Absent;
                     }