Remove standalone lines, and add one more line

Signed-off-by: Natalie Arellano <[email protected]>

buildpack.md

@@ -709,14 +709,12 @@ Given the start command and execution strategy,
       1. Firstly, in order of `/bin/build` execution used to construct the OCI image.
       2. Secondly, in alphabetically ascending order by layer directory name.
       3. Thirdly, in alphabetically ascending order by file name.
-   2. [execute](#execd) each file in each `<layers>/<layer>/exec.d/<process>` directory in the launch environment and set the [returned variables](#execd-output-toml) in the launch environment before continuing,
+   2. [execute](#execd) each file in each `<layers>/<layer>/exec.d/<process>` directory in the launch environment, with working directory `<app>`, and set the [returned variables](#execd-output-toml) in the launch environment before continuing,
       1. Firstly, in order of `/bin/build` execution used to construct the OCI image.
       2. Secondly, in alphabetically ascending order by layer directory name.
       3. Thirdly, in alphabetically ascending order by file name.
 
-The working directory for all executed files SHALL be `<app>`.
-
-1. If using an execution strategy involving a shell, the lifecycle MUST use a single shell process with working directory `<app>` to
+1. If using an execution strategy involving a shell, the lifecycle MUST use a single shell process, with working directory `<app>`, to
    1. source each file in each `<layers>/<layer>/profile.d` directory,
       1. Firstly, in order of `/bin/build` execution used to construct the OCI image.
       2. Secondly, in alphabetically ascending order by layer directory name.
@@ -727,8 +725,6 @@ The working directory for all executed files SHALL be `<app>`.
       3. Thirdly, in alphabetically ascending order by file name.
    3. source [†](README.md#linux-only)`<app>/.profile` or [‡](README.md#windows-only)`<app>/.profile.bat` if it is present.
 
-The working directory for all sourced files SHALL be `<app>`.
-
 1. The lifecycle MUST set the working directory for the start command to `<working-directory>`, or to `<app>` if `<working-directory>` is not specified.
 
 1. The lifecycle MUST invoke the start command with the decided execution strategy.