Update DocFx.Plugins.LastModified to v1.2.0

This should drastically improve docfx build time.

docs/_template/last-modified/plugins/LICENSE

@@ -19,3 +19,11 @@ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
+
+==============================================================================
+
+Humanizer (https://github.com/Humanizr/Humanizer)
+The MIT License (MIT)
+Copyright (c) .NET Foundation and Contributors
+
+==============================================================================

docs/_template/last-modified/plugins/LibGit2Sharp.dll.config

@@ -0,0 +1,4 @@
+<configuration>
+    <dllmap os="linux" cpu="x86-64" wordsize="64" dll="git2-8e0b172" target="lib/linux-x64/libgit2-8e0b172.so" />
+    <dllmap os="osx" cpu="x86,x86-64" dll="git2-8e0b172" target="lib/osx/libgit2-8e0b172.dylib" />
+</configuration>