[HDRP][Backport 21.2] Backport various PRs

[sebastienlagarde]

Purpose of this PR

• Increasing HDRP fined pruned light tile count to 63. Increasing HDRP fined pruned light tile count to 63. #5771
• Fix Upscaled Film Grain & Dither in HDRP (Fix Upscaled Film Grain & Dither in HDRP #6111)
• Fix regression that was introduced in a previous PR on the diffuse denoiser Fix regression that was introduced in a previous PR on the diffuse denoiser #6119
• Fix Light Loop Variant Warnings (1372256) Fix Light Loop Variant Warnings (1372256) #6135
• Bump the HDRP Template IET Framework Package Version Bump the HDRP Template IET Framework Package Version #6134
• Update ray tracing and path tracing docs regarding custom interpolator limitations ([HDRP][DOCS][DXR] Update ray/path tracing docs regarding custom interpolator limitations #6126)
• [HDRP] Disable DoF for orthographic cameras [HDRP] Disable DoF for orthographic cameras  #6124
• update occlusion radius for directional light sample (Update occlusion radius for directional light sample #6154)
• Clean up Public API Documentation Clean up Public API Documentation #6151
• Fix Sky override not taken into account Fix Sky override not taken into account #6127
• [Fogbugz # 1372245] Hdrp/drs fixing pyramid blur [Fogbugz # 1372245] Hdrp/drs fixing pyramid blur #6136
• Improved Area Light Support for Hair (Improved Area Light Support for Hair #6157)
• [HDRP][Path Tracing] Exposed 3 methods related to path tracing and accumulation. [HDRP][Path Tracing] Exposed 3 methods related to path tracing and accumulation. #6197
• [HDRP] Fix infitnite material import loop materials [HDRP] Fix infitnite material import loop materials #6185
• fixed typo: users -> uses (fixed typo: users -> uses #6162)
• Don't blur if nothing to blur (saves memory due to RG) (Don't call Blur shadows if there is nothing to blur (saves memory) #6183)
• Fix local fog volumes z axis calculation Fix local fog volumes z axis calculation #6068
• fixed passive voice (fixed passive voice #6092)
• AxF Raytracing: fix performance mode distillation that was broken and removed in #9d6db83478c213bc066e5f728d94b7faa6662543 ([HDRP] AxF RTR: fix performance mode distillation that was broken #6104)
• Add scale parameter in eye shader Add scale parameter in eye shader #6132
• updated Override Fog page (updated Override Fog page #6200)
• Fix missing pragma ([HDRP] Fix missing pragma #6204)
• [HDRP] Fix custom pass motion vector texture access [HDRP] Fix custom pass motion vector texture access #6205
• Fix typo in MipBias tooltip in HDRenderPipelineUI.Skin (Fix typo in MipBias tooltip in HDRenderPipelineUI.Skin #6210)
• Replace gizmos FindObjectsOfType with list registrations to avoid constant slowdown in large scenes. Merged editor guards blocks. (Replace gizmos FindObjectsOfType with static list #6168)
• [HDRP] Fix APV tooltip for Geometry Distance Offset ([HDRP] Fix APV tooltip for Geometry Distance Offset #6150)
• Fixed the point distribution for the diffuse denoiser sometimes not being properly intialized. Fixed the point distribution for the diffuse denoiser sometimes not being properly intialized. #6194
• Fixed the bad blending between the sun and the clouds (case 1373282). Fixed the bad blending between the sun and the clouds (case 1373282). #6193
• Fix shadow mask fade and optimize it at same time (Fix shadow mask fade and optimize it at same time #6083)
• [HDRP][Path Tracing] Minor fix for SSS when combined with fog ([HDRP][Path Tracing] Minor fix for SSS when combined with fog #6215)

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[github-actions]

Hi! This comment will help you figure out which jobs to run before merging your PR. The suggestions are dynamic based on what files you have changed.
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