Fix CI file revision check bug

[sneaxiy]

PR types

Others

PR changes

Others

Describe

CI check_file_diff_approvals.sh have the following bug.

~ % echo "paddle/fluid/framework/ir/graph_helper.h" | grep "paddle/fluid/framework/ir/graph.h"
paddle/fluid/framework/ir/graph_helper.h

It is because grep would use regular expression by default. To disable regular expression, use grep -F instead. See: https://stackoverflow.com/questions/9416390/grep-not-as-a-regular-expression

~ % echo "paddle/fluid/framework/ir/graph_helper.h" | grep -F "paddle/fluid/framework/ir/graph.h" | wc -l
0
~ % echo "paddle/fluid/framework/ir/graph.h" | grep -F "paddle/fluid/framework/ir/graph.h"
paddle/fluid/framework/ir/graph.h

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[paddle-bot-old]

Thanks for your contribution!
Please wait for the result of CI firstly. See Paddle CI Manual for details.

[chenwhql]

LGTM

[lelelelelez]

LGTM