pgsql: Add .gitignore to src/tutorial/

Add .gitignore to src/tutorial/

A set of SQL files are generated for the tutorial when compiling the
code, so let's avoid any risk to have them added in the tree in the
future.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8959a5e0fa2926b0f99e055e63fb4d81e1dcb3a0

Modified Files
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src/tutorial/.gitignore | 5 +++++
1 file changed, 5 insertions(+)