Add git entries for libarchive and boost in cgmanifest.json (#40155)

The OSPO notice@0 task cannot resolve licenses for components
registered with type 'other' (source tarballs). Add parallel
type 'git' entries pointing at the GitHub repos with the exact
commit SHAs for the release tags (v3.7.7 and boost-1.90.0).

The existing 'other' entries are kept for accurate provenance
tracking of the actual tarball downloads used by CMake
FetchContent. The 'git' entries enable the notice generator to
look up licenses from ClearlyDefined.

Co-authored-by: Ben Hillis <benhill@ntdev.microsoft.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: 3 people

cgmanifest.json

@@ -11,6 +11,15 @@
                 }
             }
         },
+        {
+            "component": {
+                "type": "git",
+                "git": {
+                    "repositoryUrl": "https://github.com/libarchive/libarchive",
+                    "commitHash": "b439d586f53911c84be5e380445a8a259e19114c"
+                }
+            }
+        },
         {
             "component": {
                 "type": "other",
@@ -22,6 +31,26 @@
                 }
             }
         },
+        {
+            "component": {
+                "type": "git",
+                "git": {
+                    "repositoryUrl": "https://github.com/boostorg/boost",
+                    "commitHash": "1bed2b0712b2119f20d66c5053def9173c8462a5"
+                }
+            }
+        },
+        {
+            "component": {
+                "type": "other",
+                "other": {
+                    "name": "boost",
+                    "version": "1.90.0",
+                    "downloadUrl": "https://archives.boost.io/release/1.90.0/source/boost_1_90_0.tar.gz",
+                    "hash": "sha256:5e93d582aff26868d581a52ae78c7d8edf3f3064742c6e77901a1f18a437eea9"
+                }
+            }
+        },
         {
             "component": {
                 "type": "other",