This commit introduces a CookieSerializerCustomizer callback that
allows the customization of the auto-configured
DefaultCookieSerializer bean. This is particularly useful for
configuring cookie serializer's capabilities, such as SameSite, that
are not supported by the Servlet API and therefore not exposed via
server.servlet.session.cookie.* properties.

See gh-20961

This commit changes the default builder image from
`cloudfoundry/cnb:bionic-platform-api-0.2` to
`gcr.io/paketo-buildpacks/builder:base-platform-api-0.3`. It also
uses a `paketo-buildpacks/builder` image instead of a
`cloudfoundry/cnb` image to test compatibility with lifecycle v2
and uses paketo naming instead of cloudfoundry when mocking builder
interactions.

Some adjustments to lifecycle phases were also made to align more
closely with the pack CLI.

Fixes gh-21066

Closes gh-20951

Closes gh-21068

Closes gh-20953

Fixes gh-21008
Co-authored-by: Andy Wilkinson <awilkinson@pivotal.io>

Closes gh-21170

As a follow-up for gh-21214, this commit renames the property to:

`"server.servlet.register-default-servlet=false"`

Closes gh-21214

This commit adds a new configuration property for configuring the
registration of the default Servlet in Servlet containers.

`"server.servlet.default-servlet.registered=false"`

The default of this property is still `true`, as it's been the case in
previous releases.

Closes gh-21214

* gh-21207:
  Polish "Stop limiting layer customization to external modules"
  Stop limiting layer customization to external modules

Closes gh-21207

See gh-21207

See gh-21207

* pr/21212:
  Fix some deprecations

Closes gh-21212

See gh-21212

Closes gh-20947

Closes gh-21255

Closes gh-21254

Closes gh-21253

Closes gh-21252

Closes gh-21251

Closes gh-21250

Closes gh-21249

Closes gh-21248

Closes gh-21247

Closes gh-21246

Closes gh-21245

Closes gh-21244

Closes gh-21243

Closes gh-21242

Closes gh-21241

Closes gh-21240

Closes gh-21239

Closes gh-21238

Closes gh-21237

Closes gh-21236

Closes gh-21235

Closes gh-21234

Closes gh-21233

Closes gh-21232

Closes gh-21231