docs: remove frontmatter section

Signed-off-by: CrazyMax <crazy-max@users.noreply.github.com>

docs/guides/bake/build-contexts.md

@@ -1,7 +1,4 @@
----
-title: "Defining additional build contexts and linking targets"
-keywords: build, buildx, bake, buildkit, hcl
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+# Defining additional build contexts and linking targets
 
 In addition to the main `context` key that defines the build context each target
 can also define additional named contexts with a map defined with key `contexts`.

docs/guides/bake/compose-file.md

@@ -1,7 +1,4 @@
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-title: "Building from Compose file"
-keywords: build, buildx, bake, buildkit, compose
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+# Building from Compose file
 
 ## Specification
 

docs/guides/bake/configuring-build.md

@@ -1,7 +1,4 @@
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-title: "Configuring builds"
-keywords: build, buildx, bake, buildkit, hcl, json
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+# Configuring builds
 
 Bake supports loading build definition from files, but sometimes you need even
 more flexibility to configure this definition.

docs/guides/bake/file-definition.md

@@ -1,7 +1,4 @@
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-title: "Bake file definition"
-keywords: build, buildx, bake, buildkit, hcl, json, compose
----
+# Bake file definition
 
 `buildx bake` supports HCL, JSON and Compose file format for defining build
 [groups](#group), [targets](#target) as well as [variables](#variable) and

docs/guides/bake/hcl-funcs.md

@@ -1,7 +1,4 @@
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-title: "User defined HCL functions"
-keywords: build, buildx, bake, buildkit, hcl
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+# User defined HCL functions
 
 ## Using interpolation to tag an image with the git sha
 

docs/guides/bake/index.md

@@ -1,7 +1,4 @@
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-title: "High-level build options with Bake"
-keywords: build, buildx, bake, buildkit, hcl, json, compose
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+# High-level build options with Bake
 
 > This command is experimental.
 >